A friend of mine received an inbound phone call from this toll-free phone number, and it does indeed lead back to the actual call center that placed it. The phone number is: 1866-280-9473
https://(wiped)/phonebook/dial/18662809473
They claim to be Microsoft themselves and will put up with many common scambaiting tactics, in short, they aren't very smart. He never checked if I was using a virtual machine, and wasn't suspicious of the lack of files on my desktop.
Please disrupt them as much as possible, the call center sounded quite busy in the background.