I didn't read the whole thing. I stopped when I got to what I think was more than enough information.
All in all, it seems both parties agreed to the rules of the deal, and I don't think it was an intentional scam, just a terrible idea to begin with. Why on earth would Kevin do a deal that he loses money on???
Anyway, it looks to me like Kevin thinks he is/was doing a responsible thing by being frugal with his money and not paying James on time.
But the fact of the matter is simple. Regardless of whether the money was in Kevin's or James's bank account (or neither for that matter), as soon as the due date for payment passed, that money became James's. It's not up to Kevin to be frugal with what is essentially James money. Kevin's only responsibility was to get James his money, not decide whether it was in James best interest to be paid it or not.
If the money was there, Kevin should have made payment. Anything else is bad business.
I didn't get far enough to confirm that Kevin did or didn't convey the risks of the deal with James, but from what James says he seems to have had the impression it was risk free.
If Kevin does continue to do business, I sincerely hope he learns a lot. For someone who has 14 years experience, I'm really surprised that he has allowed a relatively simple deal to go sour. He has to pay ALL debts on time. He needs to ensure people understand the risks involved (if there are any).
exsedo - It's disappointing that us younger fellows have given you the idea that integrity isn't valued. I'm 27 and I understand the concepts of integrity, honesty and what makes good business. I'm sure I'm not the only one.