Best guess on the BE supplies, items only show up there in the following Act, and not in the current one you are in.
I don't think it matters if you are full rival or friend
As per the guide here:
#1: Sundermount (Pride's End - Quest: A New Path) - Right next to the idol
Quest info: This is a companion quest for Merrill.
Mass Effect 2
Dragon Age II
Skyrim Elder Scrolls V > working on DLC.
Mass Effect 3 (oops not getting this one)