Re-wash and dry following the instructions on the Western Mountaineering website. I did that with my WM sleeping bag a year ago and the loft was better than it was when new. Note, though, it took most of a day, using my DIL's large capacity front-loading washer (with extra-delicate cycle) and dryer. If you have to go to a laundromat to use a front-loading machine, take "War and Peace" or a similar length book, plus your lunch! The drying part takes hours and hours.
Washing (properly) is actually the preferred method of cleaning a down bag. Dry cleaning removes the natural oils worse than does detergent.
Two possible sources of damage: (1) if the person used a top-loading washer with agitator, which could have damaged the baffles, (2) if the person used detergent, which would have removed oils from the down. You can probably feel if the baffles are damaged; you won't know how bad the down is until you have re-washed.
LOL, Doug, sounds like a great idea! :-)