Replaced display, now won't turn on

So, My fiance broke her screen.. I got a replacement and put it back together, but pulled too hard on the cable, slightly ripped the touch cable.. all worked except touch..

So I ordered a new display. Meanwhile I took it apart again just to make sure, checked all cables, tried holding that rip together, nothing...

Problem is, somewhere in here I did something wrong I think... Because it stopped turning on. I thought I'd wait until the new display came, but doing the same thing.

I've tried plugging into computer (nothing), charging for a bit, hard reset. Just won't turn on. Anything I could be missing, or maybe damaged the logic board?

Going to triple check all connectors but think they're good.. Thought maybe putting the logic board in the oven for a short bit to reflow it. but just waiting for now in case somebody has a better solution...