The cloud drive is mounted on the guest, yes, but once I mount it with virtiofs in order to share it with the host it gets unmounted and I end up with an empty folder. bind doesn't work either.

That would be impossible since the cloud drive is 2TB and my physical storage space is under 500GB in size.

I have no idea how it is mounted (how can I find out?) because the binary is proprietary. This is why it is contained inside a virtual machine.

The cloud drive is mounted inside a virtual machine for security purposes as the binary is proprietary and I do not want to mount it on the host (bwrap and the like introduce a whole lot of problems, the drive doesn't sync anymore and I have to relogin each time). I do not use the virtual machine per se, I just start it and leave it be.