Dell Latitude 5520 completely dead

[diamon]

I have bought a not complete and defective Dell Latitude 5520 for parts (needed the networkconnector (RJ45) to repair a other board).
Have repaired the other board (Dell Latitude 5540) and I wanted to know if I could find out what is wrong with the 5520 board (SouthPeak15 TGL MB 8L 19819-1) and perhaps repair this one also.

After connecting the USB-C charger (both USB-C ports on the laptop, does not have an other option) and pressing the power button, nothing happens (no lights or fans, no capslock).
Have checked with a thermal camera, and there are a couple of things getting hot (glowing):
DC-IN mosfet Q7408 (the other 3 staying cold)
PU4501 > creates the 3.3Volt
U2401 > mec5107

I have replaced the Q7408, but no differences.
The power button has 2,4V and with pressing the power button it is changing to 0V.
The mec5107 is getting 3.3V, don't think the issue is the chip creating to 3.3V.

According to my knowledge, the issue is a shorted mec5107 chip. I have checked the schematic of this board, these schematics are to complex for me to fully understand).
I'm I correct that the mec5107 is the issue?

I have attached some pictures and the boardview and schematic of this board.

The schematic is here: https://www.badcaps.net/forum/troubl...73#post1798173
The boardview is here: https://www.badcaps.net/forum/troubl...00#post1873600

[mon2]

Locate the RTC battery connector @ connector RTC1. Measure the voltage to ground of pin #1 on this connector = +RTC_PWR. What is the voltage? This voltage may be low and with the voltage drop through the diode @ Q2501, the voltage on the power button is 2v4. Suggest to replace the battery with a fresh one and test again.