Yeah. I agree with those who expressing a glimmer of optimism; he seems new to eBay and may have heard horror stories about Paypal or just misunderstood. You can trace a cheque to a paying account more easily than via Paypal and you have to send it to his address. As pointed out above he sounds like he knows what he's talking about when it comes to bikes.
As to the provenance of the frame? I wonder if he did buy it in the earlier auction: it was from a shop owner (?) the frame is marked up as 'shop proto 15'. It may all hang together.
Also, so far no one has piped up saying it looks the same as a Carrera Cockrocket with Orange stickers on it or anything 🙂