The fabric has been soaking in the vinegar this this am and it really seems to be helping. I've been messing with it ever 1/2 hour or so and the white vinegar now looks more like cider vinegar. EWWW! It may never be the exact yellow as it was (I can't tell because it's wet) but it's looking more uniform now. I'm planning on throwing the entire mess into the washer after I've let it soak a while longer.
So thank you all very much for your tips and insights thank goodness my thoughtlessness hasn't ruined this fabric (especially since I know exactly how I'm going to use in it my current project!) Trust me I will never store unprotected fabric in wood like that. Kinda crazy when you think that we put clothes in dressers all the time and never give it a thought.