On a knitting list it was suggested to use the cheapest brand of vodka from the grocery store. Mix 1/2 vodka and 1/2 water to get the mildew smell out.
I tried it on a 100 year old wool afghan which had been stored in a trunk in my patio room. I could see the mildew on the wool. Nothing to lose -- so I hung it on the line in my backyard and spritzed with vodka/water mixture and let it dry.
Also sprayed mixture into the trunk and left it open and in the sun to dry.
Both fine now, no smell, no mildew.
Pat