He calls in to fake hotlines that you can find in google searches and lets them mess around with a virtual machine. When it's time to pay for the "services," he furnishes them with a fake gift card or bitcoin QR code. The scammer now wants to mess around with this fake institution because they think there's a bitcoin at the other end side of the maze.

Also, once you call in a time or two you are now a proven easy mark and they will sell your number to other scam ops as a premium lead. Just like real sales!