crash to desktop-attican traverse krogan squad

im kind of screwed here. i dont have any other savegames before accepting this mission. i cannot go back to an earlier save and id prefer not to restart my progress.

im on the mission attican traverse with grunt and the rachni queen. after killing the first ravager, then opening up the reaper door with the flamethrower, there is the cutscene where the cave roof collapses. grunt says some stuff, and then game resumes. i can go either to the left or the right, its a slight hill. the second i crest the hill, my game crashes. it just says 'mass effect has stopped working', then closes. ive looked around at numerous bugfix solutions and nothing has worked. ive tried turning my graphics down to minimum, ive run the game and origin as an administrator, ive turned off the in game origin overlay. nothing is working. this is the first time ive encountered a crash to desktop while playing this game.