Quite the contrary, I think most of these treasure scammers are fairly intelligent and rational but the core of what they do is deception similar to a pick pocket or an illusionist.
If this one is investigated for fraud, I bet his records will show that he knew there was no treasure on most (possibly all) of the wrecks he scammed investors on.
One of the treasure wrecks was simply "invented" out of thin air so that his investors couldn't dispute his claims
The treasure hunt investors are the ones that get lured into a delusional state, the hallmark of a scam