Oh yeah, the fear of heights was a mess for me at that portion to. Everytime...
But 350k souls at SL35?
Do you co-op a lot, or pvp? Because I can get 18 humanity... but that's a LOT of un-spent souls for that level :o

But yeah, that part is one of my least favorite parts of the game, not because I have trouble with it anymore, but just that you have to abuse the games AI to get past it.
Alright, how I did it... (SPOILER) I ran up to the sniper on the right. When I got to the top section where you're between both archers, you dodge the arrow from the dude infront of you, and there's a section right next to the archer where the other guy won't fire at you.
From here a few things will happen...
A) the silver knight will be a complete douche and keep shooting you.
B) he'll take out his sword/shield, from here you can lure him to a safer area and try to knock him off, or just knock him off where he is and hope you don't suffer his fate.
C) he will completely screw you over, he'll take out his sword/shield, but will either hide behind his shield, or won't follow you when you try to lure him ending in him taking out his bow, and you're back to the drawing board.

Obviously you want option B.
It's a tense and stressful part, but it can go by in seconds if everything works in your favor.
Don't worry about the guy on the left, just leave him be.