Any experiences with freezing vintage furniture to prevent bugs?

Found a cool vintage couch but I am a bit worried about potential pests, which could be hiding within the cushioning. I have an option to rent out a large freezer for one week and freeze all of the soft parts at -20 degrees Celsius. I was wondering whether this is likely to destroy the cushions, which are made of Polyurethane/rubber foam assuming that I let them warm up in room temperature before using. Keen on hearing other ways to prevent bed bugs and similar pests while buying soft furniture