If you want to fix it you probably have to pull the FETs on the board, at least the high side ones. This will require hot air tools, good flux, and a good pre-heater. I have all of these, if you want me to look at it drop me a PM and I'll send you my address.
Lightfoot.
As Bitmain are not going to respond until the 25th I pulled the board anyway. There`s no obvious problems on visual inspection. Which FETs do you you mean by "the high side ones"? There seem to be four on the back of the board two marked 6040 an two marked 8040.
The high side MOSFET are the two Square chips closest to the power connector. The 6040 and 8040 are drivers because I believe that buck controller is only designed to drive one MOSFET(per side).