I'm breezing through the game with zero help whatsoever and a very rare death, that is until I have to turn the gate in Shanty Town while an unlimited number of goons are shooting at me. I even go find a secret tomb to use the camp fire save, come back to quiet music, then boom I get jumped. The worst part of it in how ever time I start twisting the wheel I get an instant barrage of fire arrows on me.

Has anyone done this on hard and have any tips? Am I screwed for leaving the area and trying to work my way back.

I would suggest clearing the area first. There are only a finite number of enemies during that segment. I had some trouble with this too but I got through it by dodging A LOT and the shotgun is your friend. 

I agree, just wait them out, kill them as they show up and you'll kill them all. It just takes a little bit. 

I made it through last night, and I can now certianly attest that this is a glitch.

Originally, I was nearly at the end of the waves when I decided to backtrack and enter a secret tomb. When I exited the tomb that confliced with the game's scipted event. Each time I tried to fight my way back to the gate I was met with goons spawning on top of me ready to blast me away. It was trial and error, but I got lucky on one attempt and no one spawned. So I basically exited the tomb, walked around the right wall and jumped the fence to get to the gate. Granted, I did the same thing a dozen times and was killed within seconds the previous 11.