happened to me a couple of months back, not as sophisticated as that though, did some guys house, got paid. next morning knock on my door 8am it was my customer, very rudely asking me do you know anything about some drunk guy demanding payment for the windows last night? (he thought i was in on it) he wasnt in his wife answered the door.
i said why would i do that, you paid there and then!
i asked did you call the police?
no i wanted to see you first to see if you knew anything about it!
he eventually left. afterwards i thought you cheeky git, accusing me of that!
dropped him after that, never liked the guy anyway
had another polski windy turn up at another custies house to try and do the windows, but my eagle eyed custie sent him packing when he realised he i wasnt due yet.