I'm facing a similar issue. Except, If I reboot the VM the raid is still there. If I reboot the host, it's gone. I have to recreate it everytime. Still no answer to the problem.
I've tried...
qm set <vmid> -virtio0 /dev/disk/by-id/<my_disk>
qm set <vmid> -sata0 /dev/disk/by-id/<my_disk>
Neither...