Ann: Massive & Disseminated Ni-Cu Sulphides Intersected, page-175

I’m not sure exactly what areas you are referring to, so it’s difficult to comment directly.
But it’s over 7km in between RC009 and RC013…including the Edmund Group sediments and several large drainage systems….so I'd be dubious about inferring much in between. The weathering profile in general across that entire area is relatively shallow…but it’s a complicated mix of essentially fresh outcrops (i.e. DRE mapped sulphides along the margins), residual weathered profiles and transported alluvial drainages.
Most ‘white’ from aerial imagery in this area I would expect to be predominantly kaolinitic, at least when developed over the Edmund Group etc, over the more mafic/ultramafic intrusions then more likely smectite. That’s not to be confused with the large pale cream ‘sheet-wash’ zones that surround the drainage systems, which imo is likely just silica rich transported sands/silts. Can always double check with Aster or Landsat etc to verify.

“If the between has broken down significant sulphides would any associated minerals carry and settle in say the river bed/low points surrounding or be diluted within surrounding rock and gone?”

The mafic intrusions are reasonably good at preserving fresh sulfide at surface...see DRE's map interep of sulfide occurrences:


That said any zones of more massive/interconnected sulfides exposed at surface will have oxidised to FeOxides e.g. goethite / limonite…if that’s in-situ then it'll be a gossan....like some of the rockchips from the Bookathanna area:


If its part of a residual regolith profile then you might have a nice geochemical anomaly, that you can detect in soils/RAB/AC etc. and in alluvial drainages or large sheet-wash transported areas that will be further dispersed and be more difficult to detect.