Contrary to what Katee says....you CAN BE "too cautious." Or perhaps it's more accurate to say that you can be "ineffectively cautious" in this industry (Ginger's sticking her nipple in your mouth comes to mind, or asking "you're not affiliated with Law Enforcement, are you?" - as if a cop must answer that question truthfully.......neither of those will give you an "entrapment" defense). Katee IS ABSOLUTELY CORRECT in saying you should trust your instincts, though.
That said - I'm not sure this qualifies as "over-cautious"....to the guy's credit, it sounds like he was "coming clean" - but it's understandable that it was too little, too late. Of course it's always nice to give someone a 2nd chance to do the right thing in the first place - but in THIS industry, it's certainly NOT something you owe him. It'll be a good learning experience for him.
If he wants to see you, he'll learn from his mistakes with you, and use that experience to get a reference or two. And of course, once he does, he can come back, right?