At first the output of the error message from the Proxmox GUI:
create full clone of drive virtio0 (vms:vm-993-disk-1)
device-mapper: create ioctl on vms-vm--109--disk--1 failed: Device or resource busy
TASK ERROR: clone failed: lvcreate 'vms/pve-vm-109' error: Failed to activate new LV.
You need to add the shared=1 option on this line. This way the container can be migrated whereby the local mountpoint will be ignored during migration. You need to make sure that the local mount point is available on every node yourself (e.g. with gfs2).