Update: After a couple of nights of soaking and saturating the ground, the big one came last nigh, algae clogged drain pipe and water breached dam. Don't know how much flow-through I had but I'd say all of it 3 times.
I now have a boat with a 6hp outboard on bottom somewhere with a solar panel mount and panel assembly with multiple other items in basin somewhere.
I'm sure by the looks of everything around pond, there can't be much for fish left. When weather clears up, I'll drain and assess it and make a decision.
22 years and never a flow event like this. It don't rain here like that, ever.