Sorry for your dilemma. If it were my car, I'd contact SoA and politely request a new engine/longblock. I'm not questioning the competency of the techs at your dealership, but swapping "seasoned" heads onto a fresh shortblock isn't a routine procedure. Just swapping over the fuel system, turbo, & accessories onto a new engine seems to me to make more sense.The sad thing is my original engine has been working well with no complaints, and i am pretty fussy. The tranny is the only issue, first the wiring harness (pre-recall) then the latest recall. The short block was not at fault, only a damned fastener with a probable burr.
I would make the proposal and see how they respond.