If you’ve got a m.2 slot in the mini PC you could add a cheap 5 sata port m.2 and connect them that way. If you don’t want to solder power you could really make it a butcher job and hack up the power from the sata to usb connectors.

Sucks to hear about your loss, I’ve recently lost my proxmox setup and migrated everything to Nixos. My install threw a wobbly, terminal was cooked, could only ssh into some containers so I wiped the install and migrated.

In my proxmox setup I found it easier to mount the drives as lvm to the host proxmox machine and pass them through to lxc via bind-mounts rather than adding another layer of shares / overheads.