I prefer to find out what the problem is, lets not forget even though the starter issue has been solved.
The problem with coolant pouring in threw the top of the intake from the throttle body heater has not.

I still need to fine that cause, if I toss another motor in it only to have the throttle body heater continue to leak I will be back were I started.
you a correct for all intensive purposes the motor is trash, but I need to know why.

I pulled the rocker covers and camshafts nothing obvious even the lifters all spun with no problem.

I think you are correct in suggesting that a valve has hit a piston,
but I have one more thing that it may be and it may explain why the intake is leaking also.

I let you know when I get the heads off.

 

I know sh*t about modern engines and even I am on the edge of my seat, wondering how all this will end. Can't wait to hear what happens next.