This reminds me of seeing footage (i think it was once done on an old oprah show) where the audience gets to try to spot a criminal re-enactment, and you basically end up with wild scenarios about what the masked-man looked like. Watch the yemaya turn out to be wearing a pink negligee. lol.
Our memories are so untrustworthy! My grandmother used to say something like, "Fetch me the blue knitting bag from the corner behind my bed," and you'd run there and back and there and back, getting her to give more details by which to identify the bag or locate it precisely in the room. Then you'd finally come back with a knitting bag, yellow with green flowers on it. She'd find a tiny brushstroke of blue in the design and say, "I knew it had blue in it somewhere..."
I also saw a great documentary once where they put a group of people around a table in a pub, and had an actor run past and snatch one of their bags. Then they took witness statements. The "thief" was described as dark-haired, fair-haired, definitely in jeans, definitely in shorts, fairly tall, very short... all from people who'd been present at the exact same incident, and all within half an hour of it happening.
It can be hard to suggest that this is what's going on, to someone who hasn't ever heard that everyone's memory plays this kind of trick. But it may be what's going on here.
Alternatively maybe he dreamt it...?
On the other hand it would be much nicer to succeed in your detective story.