Is it by chance running L/H rotation?

Nope RH.

I think this may be what is happening. The bow comes down and the prop blows out maybe because the loss of speed or maybe because now my trim angle is too great or a combination of things. I’ll see what it does with my trim at neutral I had it up a bit when this happened last

Not sure why anyone would chop throttles or aggressively cut them, there is a stern wake that can cause some issues if that happens, could actually get into some exhaust systems if you didn't have flappers. Just come off plane nice and easy and see what happens.

I hear you. I am not chopping the throttles. I back out of a pull very slowly, but sometimes it happens. Always coincides with the bow dropping. Like it was packing air but when I reduce speed the bow comes down and starts this chain reaction

Trim the drives all the way in/down before coming to a stop....if you leave them trimmed up it will fall off plane and cause severe cavitation which I believe is what you're seeing due to the bow dropping and the stern raising. If I don't trim mine down all the way before a turn or slow down it does the same thing but I have a pretty short lower on my boat so comes with the territory.

Especially since you're in a cat...it's probably dropping the bow and pushing your pocket of air out the back and when the drive is trimmed up it just spins like it's basically out of the water and trying to grab anything it can.