Here is another tip. I tried this with a suitcase that my athlete daughter used when she was gone to a week long vollebyall camp. Needless to say all sweaty gym clothes were thrown in the suitcase and then she did not immediately unpack an wash when she came home. So the suitcase had a funky gym oder. I took a clean wash cloth and soaked it in Febreze and place in the suit case and closed it. When I opened the suitcase to use a few weeks later, it smell fresh.
You could try something like this by placing the quilt and a wash cloth soaked in febreze into a basket or box and see what happens. I probably wouldn't put it in a container that is air tight (rubbermaid or zip lock bag) because the dampness on from the Febreze might develop into mildew.