hi,
see this post[0] from me, which might be related to your problem (zfs pools not getting mounted because the cachefile is corrupted or out of date)
try the solution i posted there, maybe it will solve your issue as well.
[0]: https://forum.proxmox.com/threads/update-broke-lxc.59776/post-277303
it looks like the zfs pool is getting unmounted or something, not sure whats going on, am i doing something wrong in here ? kinda disappointing
see this post[0] from me, which might be related to your problem (zfs pools not getting mounted because the cachefile is corrupted or out of date)
try the solution i posted there, maybe it will solve your issue as well.
[0]: https://forum.proxmox.com/threads/update-broke-lxc.59776/post-277303