Non-existent 3P3VAUX voltage at monitoring ADC input
The power rail 3P3VAUX that goes to CH4 of the I2C voltage monitoring ADC does not exist, probably FMC3P3VAUX was intended to be used, instead. Note, however, that according to ANSI/VITA 57.1 (p. 72) this "may be present to the mezzanine module when no other voltages are present". Since it's also used to make positive versions of 5V0N and 11V0N to allow measuring those, some small false current path might form through the resistor networks. Although that shouldn't be a problem since the current would be small, some other positive supply (or an LC-filtered version of it) could perhaps be considered, instead?