Xbox series X - no video output - previous "repairs"

So I do soldering and can do ports all day long with no issues… I received two Xbox series X from a single customer who had sent them to other people first … one had one of those classic horror solder jobs… the other was just meh. The one that was the worst is grounding out on one of the data line, so I replaced the re-timer chip and that did not fix the issue. No bad caps / corrosion / iffy looking parts… so what now? Is the APU bad?

box # 2 does not have the shorts on the data line, but still no display. wish I had a schematic.