How to restore partitions on a failed LVM?

Question

linux

I encountered an obvious LVM glitch, and I did not find any similar cases and instructions on what to do in this case.
The story is this: there was a server on Ubuntu 16.04 with LVM over mdraid on 9Tb. The lvs structure is something like this:
root 25Gb
swap 8Gb
virt1 100G
virt2 100G
bigdata 5Tb
And I also created a lvm volume "virt3" for 25Gb, and uploaded the image there.
The first bad call was that virt-manager showed the size of 5Tb for the virt3 volume. But lvs showed everything fine. After rebooting the server, everything became completely sad: the system considers the volumes virt1, virt2 and bigdata to be empty,
e2fsck does not see the superblock, testdisk does not see the files when selecting any found superblock (didn't do a deep scan - it took a very long time). Strangely, the root partition is in perfect order.
As far as I can tell, something went wrong in LVM, and the image was written to the wrong partition, but touched several others.
Now I launched a scan in R-Studio, but it sees the lvm partition as a RAID, which suggests that nothing will come of it.
What else to try?