I thought I'd chip in here for the reason that I found this a total pain to get through. I must have spent about an hour trying to get past this point and reloaded about thirty times. In the end it was quite simple. I just used the time honoured method as mentioned by the OP, but I'll expand a little. You have four sets of supports to collapse - it's important that you do all four since this will affect how quickly the kikimores come and find you, it seems to be inbuilt in the game. It seems that if you leave one set out, they come quicker. So do them all regardless.So1 - Run under the first support, turn round, shoot it with the aard. When you see it dropping, run to the second set.2 - Collapse the second set [of course you have to be slightly in front of it], don't wait for the queen, just do it anyway. Loot the corpse if you feel you have time, but you don't have to. It's really important that you collapse the first two even if you feel you don't need to since the kikimores will come a lot slower at you if you do this. 3 - Run into the main cave area ahead, you will see the kikimores spawning. Turn around and collapse the third set. 4 - Run to the right, avoiding all the kikimores, wait till you're slightly ahead of the final support [it should be obvious which it is] and charge your aard fully. Direct it at the last support and wait for the cave to collapse. Don't worry, it won't collapse on you no matter how long you wait and even if it's all shaking around you. Sorry if I'm just reiterating stuff but this part of the game really isn't that hard. If you just do all the supports in sequence it is a lot easier. I found the kikimores got in the way too soon, stopping me from succeeding. They come a lot slower if you collapse all the supports behind you, even if you feel it's not necessary.