Slynkyr

I had this same exact problem a couple weeks ago or so. I didn't abandon it because then I would have to kill the yetis for the quest items all over again. I left the zone and did some other questing and came back in a couple of days to try again. It somehow fixed itself and let me turn it in. I don't think I did anything unusual to make this happen, he had the yellow "?" instead of gray when I returned and it worked as it should.

I found this old topic while looking for a solution because I had the same problem. When I tried it a second time I got the idea to try to complete the quest even though there was no lightning strike, and it worked! So the issue is that the lightning strike seems to have not been scripted into the quest, but you can still complete the quest by clicking on the bramble once you get it on the stone. Notice that it is glowing as if it's electrified. And you must click the bramble and not the stone. Clicking the stone is for the Princess quest chain and not related to this. Also, you can get the sticks from any of the trolls, headhunters, axe-throwers, witch doctors, etc. They all drop them at a good rate and it only takes a few minutes.