Ciao,
suppongo che l'eseguibile riportato sia usr/libexec/nm-initrd-generator.
Puoi copiare qui l'output del seguente comando?
sudo mkinitrd -f /boot/initramfs-5.15.74-1mamba-x86_64.img 5.15.74-1mamba-x86_64

Ciao !
Chiedo scusa per gli errori di trascrizione....

Ecco l' output del comando suggerito :

" dracut: Executing: /usr/bin/dracut -f /boot/initramfs-5.15.74-1mamba-x86_64.img 5.15.74-1mamba-x86_64
dracut: Including module: bash
dracut: Including module: systemd
dracut: Including module: systemd-initrd
dracut: Including module: modsign
dracut: Including module: dbus-daemon
dracut: Including module: rngd
dracut: Including module: dbus
dracut: Including module: i18n
dracut: Including module: network-manager
dracut: Including module: network
dracut: Including module: drm
dracut: Including module: plymouth
grep: /usr/share/plymouth/themes/text/text.plymouth: No such file or directory
grep: /usr/share/plymouth/themes/text/text.plymouth: No such file or directory
The default plymouth plugin () doesn't exist
dracut: Including module: btrfs
dracut: Including module: crypt
dracut: Including module: dm
dracut: Skipping udev rule: 64-device-mapper.rules
dracut: Skipping udev rule: 60-persistent-storage-dm.rules
dracut: Skipping udev rule: 55-dm.rules
dracut: Including module: dmraid
dracut: Including module: kernel-modules
dracut: Including module: kernel-modules-extra
dracut: Including module: kernel-network-modules
dracut: Including module: lvm
dracut: Skipping udev rule: 64-device-mapper.rules
dracut: Skipping udev rule: 56-lvm.rules
dracut: Skipping udev rule: 60-persistent-storage-lvm.rules
dracut: Including module: mdraid
dracut: Skipping udev rule: 64-md-raid.rules
dracut: Including module: multipath
dracut: Skipping udev rule: 40-multipath.rules
dracut: Including module: nvdimm
dracut: Including module: qemu
dracut: Including module: qemu-net
dracut: Including module: cifs
dracut: Including module: fcoe
dracut: Including module: fcoe-uefi
dracut: Including module: iscsi
dracut: Including module: lunmask
dracut: Including module: nbd
dracut: Including module: nfs
dracut: Including module: nvmf
dracut: Including module: resume
dracut: Including module: rootfs-block
dracut: Including module: terminfo
dracut: Including module: udev-rules
dracut: Skipping udev rule: 40-redhat.rules
dracut: Skipping udev rule: 50-firmware.rules
dracut: Skipping udev rule: 50-udev.rules
dracut: Skipping udev rule: 91-permissions.rules
dracut: Skipping udev rule: 80-drivers-modprobe.rules
dracut: Including module: virtiofs
dracut: Including module: dracut-systemd
dracut: Including module: usrmount
dracut: Including module: base
dracut: Including module: fs-lib
dracut: Including module: memstrack
dracut: Including module: shutdown
dracut: Including module: uefi-lib
dracut: Including modules done
dracut: Installing kernel module dependencies
dracut: Installing kernel module dependencies done
dracut: Resolving executable dependencies
dracut: Resolving executable dependencies done
dracut: Hardlinking files
dracut: Mode: real
dracut: Method: sha256
dracut: Files: 3701
dracut: Linked: 175 files
dracut: Compared: 0 xattrs
dracut: Compared: 2304 files
dracut: Saved: 15.54 MiB
dracut: Duration: 0.355898 seconds
dracut: Hardlinking files done
dracut: Generating early-microcode cpio image
dracut: Constructing AuthenticAMD.bin
dracut: Using microcode found in '/boot/intel-ucode.img'
dracut: Store current command line parameters
dracut: Stripping files
dracut: Stripping files done
dracut: Creating image file '/boot/initramfs-5.15.74-1mamba-x86_64.img'
dracut: dracut: using auto-determined compression method 'gzip'
dracut: Creating initramfs image file '/boot/initramfs-5.15.74-1mamba-x86_64.img' done "

Grazie.

Ciao,
l'errore nell'installazione del modulo network-manager di dracut dovrebbe essere corretto con un aggiornamento di NetworkManager. Una volta effettuato questo aggiornamento dovresti eseguire nuovamente il comando sopra indicato per rigenerare l'initramfs.
L'output di dracut riporta un problema con il bootsplash, a meno che non sia intenzionale averlo impostato in modalità testo puoi controllare che il file /etc/plymouth/plymouthd.conf contenga:

[Daemon]
Theme=breeze

Ciao !

Nonostante l' aggiornamento ed aver rigenerato l' initramfs il messaggio d' errore si è ripresentato.

Riporto il report dopo le operazioni :

" dracut: Executing: /usr/bin/dracut -f /boot/initramfs-5.15.74-1mamba-x86_64.img 5.15.74-1mamba-x86_64
dracut: Including module: bash
dracut: Including module: systemd
dracut: Including module: systemd-initrd
dracut: Including module: modsign
dracut: Including module: dbus-daemon
dracut: Including module: rngd
dracut: Including module: dbus
dracut: Including module: i18n
dracut: Including module: network-manager
dracut: Including module: network
dracut: Including module: drm
dracut: Including module: plymouth
dracut: Including module: btrfs
dracut: Including module: crypt
dracut: Including module: dm
dracut: Skipping udev rule: 64-device-mapper.rules
dracut: Skipping udev rule: 60-persistent-storage-dm.rules
dracut: Skipping udev rule: 55-dm.rules
dracut: Including module: dmraid
dracut: Including module: kernel-modules
dracut: Including module: kernel-modules-extra
dracut: Including module: kernel-network-modules
dracut: Including module: lvm
dracut: Skipping udev rule: 64-device-mapper.rules
dracut: Skipping udev rule: 56-lvm.rules
dracut: Skipping udev rule: 60-persistent-storage-lvm.rules
dracut: Including module: mdraid
dracut: Skipping udev rule: 64-md-raid.rules
dracut: Including module: multipath
dracut: Skipping udev rule: 40-multipath.rules
dracut: Including module: nvdimm
dracut: Including module: qemu
dracut: Including module: qemu-net
dracut: Including module: cifs
dracut: Including module: fcoe
dracut: Including module: fcoe-uefi
dracut: Including module: iscsi
dracut: Including module: lunmask
dracut: Including module: nbd
dracut: Including module: nfs
dracut: Including module: nvmf
dracut: Including module: resume
dracut: Including module: rootfs-block
dracut: Including module: terminfo
dracut: Including module: udev-rules
dracut: Skipping udev rule: 40-redhat.rules
dracut: Skipping udev rule: 50-firmware.rules
dracut: Skipping udev rule: 50-udev.rules
dracut: Skipping udev rule: 91-permissions.rules
dracut: Skipping udev rule: 80-drivers-modprobe.rules
dracut: Including module: virtiofs
dracut: Including module: dracut-systemd
dracut: Including module: usrmount
dracut: Including module: base
dracut: Including module: fs-lib
dracut: Including module: memstrack
dracut: Including module: shutdown
dracut: Including module: uefi-lib
dracut: Including modules done
dracut: Installing kernel module dependencies
dracut: Installing kernel module dependencies done
dracut: Resolving executable dependencies
dracut: Resolving executable dependencies done
dracut: Hardlinking files
dracut: Mode: real
dracut: Method: sha256
dracut: Files: 3801
dracut: Linked: 175 files
dracut: Compared: 0 xattrs
dracut: Compared: 2327 files
dracut: Saved: 15.54 MiB
dracut: Duration: 0.365060 seconds
dracut: Hardlinking files done
dracut: Generating early-microcode cpio image
dracut: Constructing AuthenticAMD.bin
dracut: Using microcode found in '/boot/intel-ucode.img'
dracut: Store current command line parameters
dracut: Stripping files
dracut: Stripping files done
dracut: Creating image file '/boot/initramfs-5.15.74-1mamba-x86_64.img'
dracut: dracut: using auto-determined compression method 'gzip'
dracut: Creating initramfs image file '/boot/initramfs-5.15.74-1mamba-x86_64.img' done
"

Grazie.