Section 110.10(B) requires listed or labled equipment to be installed in accordance with any instructions included with the listing.
While only UG or UV conductors need to be listed, most conductors are listed anyway.
When the UL White book is consulted, it turns out: "Conductor Termination Compound — Some connectors are shipped pre-filled with conductor termination compound (antioxidant compound). For non-prefilled connectors, conductor termination compound may be used if recommended by the connector manufacturer as preliminary preparation of the conductor."
The recommendations I have read always prescribe oxide inhibiting compound for damp or wet locations with aluminum wires.
