Looks like one failure-prone part has already been replaced. The fuel pump looks new?
Does the negative battery cable have a connection to the body? If not, and it only goes to the engine block, you might want to add one. Maybe some 10ga wire between the battery cable and wheel well at the starter relay or similar setup.
Sorry to hear of your hassle, but you can thank the internet and modern pirates for that. Hasn't been a worry-free cashier's check transaction in more than 10 years now. Every Tom, Dick and African prince is sending out bogus cashiers checks these days.
I'm sure when you hand one off directly, and it goes down at a bank, it's probably less of a problem. But I can understand why they're no longer considered just as good as cash by some anymore.
Paul