Dracut fails to boot root-fs

Dear list,
Gentoo has been my distribution of choice for more than 20 years, I 
borked my systems more than once but always found a solution eventually.  
Not so now.
Some time ago I aquired a refurbished Gen. 3 HP ZBook as a replacement 
for my Very Old Laptop. I installed Gentoo following the handbook and 
the relevant wikipages covering LVM and encryption of the root 
filesystem. It failed to boot. As I couldn't figure out what I had done 
wrong I installed Devuan to be sure not to have a hardware issue. That 
booted perfectly fine. So I did a complete reinstall on the partitions 
left over from Devuan. An efi-partition, a boot-partition and a big 
LUKS-encryptet partition with a swap and a root vg.
Again, I could not boot the root fs.
After meddling for a while without success I figured, that I am just too 
dumb for LVM and that my thread model allows for unencryptet swap. Again 
I did a complete reinstall after repartitioning, this time without using 
LVM.  The problem persists.

The installation went smoothly and the chroot works as expected. I use 
GRUB as bootmanager and sys-kernel/gentoo-kernel-bin to rule out 
configuration issues. GRUB loads the kernel without problem and I am 
prompted for the luksOpen passphrase. After entering the correct 
passphrase nothing happens for several minutes until I am dropped into a 
dracut rescue shell.
It states:
dracut Warning: Could not boot.
dracut Warning: /dev/disk/by-uuid/73afXXX does not exist

I can mount and access the root filesystem (/dev/mapper/cryptroot) 
without problem but even after mounting it on /sysroot and exiting the 
shell it fails to boot and drops me right back into the shell. 

dracut:/# blkid
/dev/nvme0n1p3: UUID="66b9XXX" TYPE="swap" PARTUUID="7f17XXX"
/dev/nvme0n1p1: UUID="C900XXX" BLOCK_SIZE="512" TYPE="vfat" 
PARTUUID="9f76XXX"
/dev/nvme0n1p4: UUID="332dXXX" TYPE="crypto_LUKS" PARTUUID="52a0XXX"
/dev/nvme0n1p2: LABEL:"boot" UUID="aef0XXX" BLOCK_SIZE="4096" 
TYPE="ext2" PARTUUID="c457XXX"
/dev/mapper/cryptroot: LABEL="root" UUID"73afXXX" BLOCK_SIZE="512" 
TYPE="xfs"

dracut:/# cat /proc/cmdline
BOOT_IMAGE=/vmlinuz-6.18.18-gentoo-dist root=UUID=73afXXX ro rd.lang=de 
rd.vconsole.keymap=de-latin1 rd.luks.name=332dXXX=cryptroot

I tried to modifie the GRUB commandline to access the root filesystem by 
LABEL or by /dev/mapper/cryptroot with the same effect.
Everything seems to work: GRUB, the initramfs, cryptsetup... so I don't 
have an idea what's going wrong. Only thing is, there is no entry for 
/dev/mapper/crypt in /dev/disk/by-uuid and in /dev/disk/by-label.

Anyone pointing me to the Obvious and Stupid mistake I'm making (or 
giving me other meaningfull advice) would be greatly appreciated.   

Kind regards

Carsten