Recently tried the freezer idea for 24 hours, with two older scarves that brought odors from their former homes. Freezing in separate bags seemed to lighten the smells but not eliminate. I bought a packet of “odor eliminator” sachets that were incredibly strong in themselves, leaving their own “residue” but the former fowl sniffs were gone. Now the two are separated in a drawer with lavender sachet to see what happens.
Washing and airing had worked for a while but enclosure in the drawer during summer had restarted and spread the odors to other silks as well. Everything else aired out, but the two problem children wouldn’t let go their odors.