I was up to camp Schurman 2 weeks ago. I wouldn't recomend traveling the route without crampons, rope and axe. I am not familiar with Mt Ruth, but if it puts you up to Camp Curtis, then it is possible to continue up the exposed rock ridge right up into Schurman but to get into camp you'll have to descend some pretty loose rock above the hut. Some folks that didn't like the shape of the Emmons left that way while we descended the Emmons. They claimed "No problems" getting to Camp Curtis