please continue in the original topic you opened instead of creating a new one. PolSARpro ALOS2 FDB analysis
Did you try to visualize the C2 matrix with the BMP creation tool?
Actually, calibration and geocoding are not required before the HA decomposition.
In the PolSAR training materials here, the data is terrain corrected by the SNAP binaries from within PolSAR pro, but this is optional (slides 75-79). The slides refer to quad-pol data but it is the same procedure and they are very detailled.