Yes, it sounds a lot like a heart attack, especially given the details you shared.
In a way, in the grand scheme of things, I envy him. First, it didn't happen while he was flying (or landing) with a plane full of people. Kudos to him for that! Second, he was in a place that he loved and doing something (riding his bike) that he also loved. I can only dream of being so lucky when I go. Doesn't make it any easier for the folks left behind though.
He's likely laughing his tail off at the irony of the Irma situation. Here he beats the Lister drum for years and then misses the big storm by two weeks when it finally arrives...
Again, I'm sorry to hear of your loss. I searched for an obit. following your first post but wasn't able to find one. I figured it would be interesting reading based on his contributions on this site. I watched all of his vids years ago. Thanks to your post, I re-watched them all again. He was a good guy that was talented and did beautiful work. He will be missed.
Glad things aren't out of control where you're located. I've been checking the Jupiter webcam periodically and sending positive thoughts. Hopefully it stays mellow. I think it was very smart to prepare though because it could just have easily tracked up the east coast instead.
Hang in there and please keep us updated.
Steve
(Rocketboy doing his thing)