SCN - may be a S-ligand or a N-ligand. The first, in my opinion, will form a covalent Fe-S bond, thoutgh in the crystal structure it can form a donor bond N...Fe. For more than one SCN groups one can expect both S-Fe and N-Fe coordination at the same atom.
See: K.Pohl, K.Wieghardt, B.Nuber, J.Weiss (1987)
J.Chem.Soc.,Dalton Trans.,187