Despite their brutal reputation, the Orks are just... sitting there. Hm.
That's hard to gauge from the sidelines; try listening in on their conversations.
Oh, right. Perhaps your companions do? ?
Speak to Nuri.
Apparently they're waiting for a 'sign' from their god, Tairach, and getting quite impatient.
That's not very clear from here - try exploring in the area to the left.
(Don't worry - the Orks won't see you!)
Most notably - a gigantic Tairach statue in the distance. You can get closer to it by proceeding up the path on the left.
The Shaman from the previous area is performing a ritual and clearly expects it to illicit a response from the statue; if we could 'fake' a response, that would certainly shake things up in the camp.
The flowing water nearby could be used to make the statue 'cry', if we diverted it somehow.
Try looking for something that'll help us cross the nearby gap.
Something long enough to bridge the gap, and sturdy enough to hold Geron's weight.
There's a good chance of finding something like that in the camp.
Return to Nuri's hiding spot, then grab the wooden board on the floor - it's between her and the horse.
Use it to cross the 'abyss' and get closer to the statue.
The ultimate goal here is to divert the water flow - see these hints for help with that.