PS5 Controller won’t turn on

I have a ps5 controller from a friend. I don’t know where he got it, but I opened it up and there it was a missing ribbon cable that connects the motherboard on the left side with the dpad. It also will not power on no matter what I do. I swapped the batteries out and the batteries were fine, I cleaned the face button mapper and everything else. I would like advice on what to do?