Board came in very liquid damaged. Replaced everything on the top of the board for 3v42, replaced Q7010, R7012 (was blown), the ISL and all controller fets (thinking it could pull DC in down as it did on a board I fixed yesterday), and ultrasoniced. Also touched up J9500 area of corrosion, and STILL only 3.1 volts on DC in. I'm completely out of ideas on what could be causing this no short on DC in or 3v42 or PPBUS.