Tomb Raider Legend Weird Bug in Kazakhstan Boss Fight

Firstly, this is on PC. This is a "bug" that happened to me accidently. Maybe this has something to do with my PC, i don't know. but when i tried the second time, i managed to create it once more. As you can see the soul reaver cheat is on (the bulletproof lara and one shot kill cheat were on too but i'm not sure if they're relevant) After pulling the 4 levers in the room attack the unknown entity couple of times and it'll disappear! Then mount the Tesla gun and push those giant "half globes" with it (as usual). The shield covering the sword fragment will dissapear, the glass on the floor will break but you won't be able to get the fragment so Lara will be stuck in that room forever!!!!!! (and btw with this method you can make her walk on air without any special patches or, programs :P i hope)