@juanwriter So, you always work on a VM? That’s cool. Windows has a VM mode feature, and it is high on security, too (cuz they are all VMs after all).
Yes, I use Manjaro as host, and VirtualBox with several VMs, each for a dedicated task (Office, Photoshop, Firewall, Extra security one for sensible data treatment, and a sandbox for checking suspicious files). Security rely on host. You can have the VM on Windows, just make sure the host is never compromised and well protected (that is, don’t browse the internet on the host, or only go to safe websites)
Dude I were at your place then I would block the buyer and go to my way, I strongly suggest you not to reach CS for any kind of issue.