Ann: Carr Boyd Nickel Sulphides Continue at Depth, page-67

Para 1 - yes. Perhaps the EM is 'finding' pyrrhotite richer areas - there may be other zones where pentlandite, chalcopyrite are richer. Layered intrusive Ni/Cu/PGM deposits can have marked zonation. This was discussed in the 1972 paper (which is excellent and written by a number of noted (academic and field) geologists)
The step out drilling will/will not confirm (yes lots more work to do)

Para 2 - conductivity and magnetism do have an inter-relationship. Lorenz and Faraday will confirm. A mineral may be none of these, either, or both. A mineral that is both (pyrrhotite) will give stronger EM response.

Anyway lets see what hole 43 hits ( an important hole towards any size extent)