LVM not seen

[Grizzly]

Hi All

probably astupid question but here goes

Just added a (forth) HD to my current PC, each HD had an OS (taken from failed 
Laptops) two have since been upgraded to later Ubuntu versions (24.04 & 24.10)

The latest HD was added to test ElementryOS 8 (question not about ElementryOS) 
without changing my other OS's

Install went fine, (it uses Noble repos) Elementry Grub "sees" three of my HD's 
(itself & 24.04, 24.10) but not the Win7 JHD (no problem really)

BUT both 24.04 & 24.10 grub does not "see" the Elementryos

GRUB_DISABLE_OS_PROBER=false

I did run 

sudo update-grub on both boxes

once booted both mount the Elementryos boot partition but dont see the data 
partition (LVM)

disks (obviously) shows te data partition as Type "lvm2" but does not AFAICS 
allow setting mount options

I would like (if possible "without risking loss of data") to 
1) choose elementry from Grub (either 24.04 or 24.10)
2) see elementry data partition from 24.04 & 24.10

I have installed lvm2 on 24.04 & 24.10 but even after searching around I cant 
find how to "just" mount it