Top board not booting

Hello guys, I got some issues with the iPhone from my aunt. She used a non-genuine adapter to charge it and burned the logic board.

I have a DC power supply and when I give the phone 4V and 3.3 AMPS it doesn't boot. I use QianLi icopy. Nothing is getting significantly hot, I couldn't measure any short on VDD main, that's why I separated the board and still it won't boot.

The DC ps shows 0.00 AMPS constantly.

The only thing that gets slightly hot for a very short time is the USB management IC, but it can only be seen through ICE spray.

I also suspect the PMU to be faulty, but there would be a short then right? I attached a picture of the PMU IC, its corners look "melted". I also noticed missing caps next to the CPU but I'm sure the phone hasn't been opened up before.

do you have any ideas what else I could measure?