I use also fuse-overlayfs for one of my Docker Container and PBS Backup working without problems.
Except only a couple warnings:
"failed to open /var/lib/docker/fuse-overlayfs/b4e3f337e5fb6b2517e1a85bab9e78235b97a501b6984525dd5cf6778a2a1dfb/merged: Permission denied"
Proxmox: single node, no...