Rotational axis for Fe I: 3X4-fold rotational axis (in x,y,z case as rotation axis there are 4 orientations when the lattice looks the same)
Same situation is with Fe II lattice.
This is because the crystal lattice is cubic, not tetragonal (cubic along 2 axis and rectangular along the third) as in the case of Indium
In this case eta n = 0 & EFG = 0.
From my logic all 3 axis can be takes as PAS as there is no way to distinguish the changes due to rotation along any of them.