All routes on Rainier have suffered badly this year from tons of warm temps and excessive melt. This has exposed LARGE areas above 10,0000 of black, old, glacier ice that many have reported and I've experienced as somewhat bulletproof to pro. The Mowich is melted out with large amounts of exposed 50 degree+ loose scree, rock extremely prone to fall and virtually impossible to protect and the upper section hard exposed ice. This would make climbing it an effort in becoming a human bowling project with you being the pins. Last I checked with the climbing ranger staff there had been no recorded summits of the route this season and if correct no attempts given the status since at least mid July. Add to this the road closures, extended distances of approach, trail damage, and few to no potential rescuers left this late in the season, and hence the view that it might be risky to the point of ridiculous. Try calling the climbing ranger team left there and ask directly about any other advice or updates.