Never use fabreeze or any dryer sheets on anything! They just mask odors and they also collect odors over time that are even harder to get rid of.
I agree that Vinegar and Baking Soda are your best bets. Make sure you dilute each of them well. Both products dissolve the dirt molicules and neutralize the odors naturally, and neither should harm your fabric. Both also soften the water, so that it cleans better. Oxyclean does basically the same thing and uses a stabilzed oxygen to dissolve the dirt molicules and neutralize odors.
If the quilt is off white or white, then you could use 3% hydrogen peroxide well diluted to soak in as well.
Always rinse very well, and dry outside as others have suggested.