Ok pulled the head. here’s the inside:
you can see the one black Cyl1.. I’m guessing its black because of unburned oil and carbon and water combining? or just misfiring
it’s REALLY hard to see but here is what looks to be Failed head gasket location.. This doesn’t have a actual broken gasket (hence why compression stayed above 123psi?)
this is a tough debug… but you see how the metal contact part of the head gets shiny and polished.. it’s vibrating there and not firmly Connected to the gasket at that point.. each power and exhaust stroke it’s expanding and contracting.
it will never burn thru because on every stroke it’s getting some fresh cooling water past it..