OK, well the head gasket is definitely blown:
The head looks OK, don’t see any obvious dimples:
This next picture is most telling. I don’t see any obvious dimples from rings banging around, but have a look at the exhaust side of the piston, looks worn away. There is a large gap between the cylinder wall and piston on the opposite side which would explain the excessive side slop. I’m thinking the rings just slipped out of the exhaust ports without leaving the obvious dimples in the head/piston dome:
The next pictures don’t show much, block deck surface looks OK though:
So, I really fear this piston is toast, even though I don’t see the usual dimples from rings mashing around in the combustion chamber. I suppose it is possible that the broken ring pieces just snuck out the exhaust ports. You have little to lose (except the cost of a new head gasket) if you want to try replacing the head gasket to see what happens. Again, I sure hope I’m wrong. Don
