Wait: you went up the right-hand section of this track and came down on the left? Looking for the pack well off of the ascent track? I guess the light was better over there later in the day.
When you say "half way up the ridge, do you mean ON the ridge half way up that section of your route, or half-way up TO the ridge?
Either way, it seems that the pack is somewhere on the right hand section of the loop, and not in the area you have marked.
Maybe you could clarify this by marking your direction of travel, ascent, descent, turn-around point, etc.
