I was running a 56' Neptunus motoryacht thru the Alligator-Pungo canal years ago, late in the season, but on a bright sunny day... I come up on a 51' Formosa/Island Trader Captain Ron machine plowing along at almost 8 knots...
I've got to say Jon that seems a little mean to me too. Just because the guy misjudged things a bit and figured it would be safe to let you pass while he was at the bow I don't think he deserved to be blown off the road.
Don't forget if he waved you off you would not have the the right to pass at all. You legally have to get the forwards boats permission to pass inland.
So he was trying to be a nice guy.
Thinking of alternative you probably could have drafted him about 30' off his stern with no danger to you and 5 tooted him until he came back to the helm and radio to find out what the commotion was all about.
Frankly I don't think a guy with your credentials would do this again. I suspect you underestimated the wake and the result of the wake also.
From a legal point of view if you did what you did and he hit a submerged pole and sank his boat I suspect the the court would assign some significant part of the blame to you because despite the other boats errors you would be considered the aggressor.
But thanks for posting this as it shows that even our most experienced captains can sometimes in a split second make a bad call.