I personally like the Dryell, but how well it works depends on several things.
1) How strong the smoke smell is
2) What setting your dryer is on.
3) What the material is (I know you said unknown)
There are three things I do to prepare my clothing for listing. First, I hang it on my back porch for a couple of days (yes, it is screened in). Then I use the dryell.Finally, I use Fabreez on the item. Since I have done these things, I have not had any complaints. I do not state " From a smoking House" or "From a Smoke free home". Other sellers I have spoken with say that their sells have dropped when saying both. I leave it as Please ask any questions you may have. Yes, I do have several people ask if my item are from a smoke free environment. My answer is always, "I cannot guarantee my items to be from a smoke free environment. I purxhase items used and thus cannot say what environment they were in prior to my purchasing them." I tell them what lengths I have gone to, to ensure their freshness, but never make any guarnatee, because my sniffer may not be as sensitive as other peoples. Anyway, I didnt mean to get off on all of that, just make some suggestions for getting them smelling fresh. Fabreez works much better than Dryell in my opinion. I have stated spaying my items with it before ironing them. The heat from the iron really seems to seal in the fresh scent.