I wish you'd had some to and fro. That would have been most entertaining. There was a gumtree scam in Australia some years ago if you were trying to sell a vehicle on there; my mate was trying to sell his scooter. Basically they would pay you top dollar to ship it Asia somewhere. I can't remember the details but my mate played along for ages to the entertainment of everyone in the office.
I have read some cracking play them along ones like that. It is the kind of thing I often do. With this one I am tempted to let sleeping dogs lie. They seem quite professional almost so I think they would suss right away and there wouldnt be much fun to be had