Overheating, won't Start after screen replacement. BUT AND MORE!

Customer brings in 2 x Samsung S6 Phones

1. Water Damaged (previously repaired) Screen

2. Damaged Screen

Please make one good one out of these two please, is the request

No Worries I say and get to work

#1, Pulled down. Main Board stuffed as well as Screen

2. Yep, definitely a broken screen Put on a new screen

Went to turn on and nothing ..... at all, yet before the screen was replaced the touch keys lighted and one could see the Blue light come on but there was no kick from the Vibrator motor. At the time that made me raise my eyebrows

At this time I put the phone on charge. Gave it a couple of minutes and checked it with a heat gun and the temp was up to 53c at the top of the phone, under the Camera, Bat was cool, anyway changed Bat, still heating up, changed charge port but tested out of the frame. Temp shot up to 70c ( maybe being out of the frame, nothing to soak up the heat) anyway disconnected the battery and sat on my hands!

Got on the net and asking Q's