Ok, so i kept digging.
it seems that my new VG (vg01) didnt have a LV created, so i could create one.
now i have the LV0100 attached to vg01 (my new disk alone)
and LV0000 my old LV attached to vg00(my old RAID6 disks, + the 2 news)
on this LV0000 i created a "test" share, but i dont see any of my old shares.
if in the CLI, i set the vg00 as default, each time i boot, i get the message "ERROR: No system volume found! System services can't work without system volume !"
in the WEBinterface, when i want to access my share :i have aswell : "Warning No system volume found."
there is an option in the CLI that i didnt try "restore LVM VG (volume group) configuration"
do you think it might help ?
This maybe more complicated from the RAID array, you may need to contact the RAID vendor and provide them logs and explain the sequence of what happened.