In CU199 it was reported that Qemu vm’s were not starting but that was due to a missing libfuse library due to a peculiar versioning process that libfuse uses.
As CU199 had already been released when this was reported, then the fix for that problem was implemented in CU200 which is out currently for Testing.
I am not familiar with qemu or qemu-ga and don’t/haven’t used them so I am not sure if the libfuse library issue could also result in that file being missing.
Maybe you could test out CU200 Testing and see if that solves the problem or not.
The package is working fine on me. It looks like you don’t have support for it enabled on the hypervisor and therefore the VM does not have a device to connect to the hypervisor with.
If you are using Proxmox, it is a checkbox in the settings of the VM.