BSOD further diagnosis help required

I have a NS here which has BSOD, it’s my first switch repair. I have checked to following:

All rails on MAX77620 seem as expected during first boot.
One of the MAX77621 is up (AIUI the other one near the wifi doesn’t start until second stage)
3v3 from ENxx chip seems good.
eMMC data line pulses 20x as per F1 on Retrosix wiki.
eMMC clock runs during first boot and then stops.
Total input current at 4.2v is 200mA with bare board
After removing eMMC it enumerates on USB for RCM but it is a newer machine so I don’t think I can inject anything.

I would be grateful for ideas of where to check next.