I used an old Synology with 9 disks in raid 5 (i know it's my primary error to have a raid 5 with so much disks) and i lost 2 disks in same time, Raid failed and Synology was unabled to rebuild it.
Raid volume was used as iSCSI target for VMFS Datastore, but disk are not physically damaged or noisy, Smart data are fine.
I put all disks in Windows with a SATA Controller :

I load TestDisk and i try to recover partition on disk0 and disk1.
disk0

disk1

If i continue with "Enter" i have only one partition (same on disk0 / disk1) :

I did the test on others disks and i have same result, only one partition is displayed at this step.
Do you think i can continue with "write" or it's better to move to Ubuntu to have "mdadmin" tools too ?
Aonther solution could be to replicate partition table from a working disk (with sgdisk for example)
Thank you in advance,
Yathus