It's a lovely quilt...maybe you could just raffle it, that should raise a bit. Perhaps the group should separate the obviously more valuable donations and sell them separately, either online or via local trading posts or whatever.
I am a great rummager and charity shop treasure hunter, if I see something marked too low or I know it is collectable I always offer more and if it's not of interest to me...tell the workers so they can decide what to do with it. It is amazing what turns up in charity stores...and purchasers need to realise it's for good works, not a business.