hello Graham...
Now I must confess that I am a 'smoker'... but only in certain places... like in front of the exhaust fan, and out doors.....
But... I have developed a lot of expertise in cleaning and restoring... so..
IMO.. if the smell is latent in the old seasoning, then I would bet that the seasoning was beginning to 'turn' thru lack of use, and allowed the 'smell' to be absorbed.
I would strip completely and restore. That will git er done for sure.
My Grandmothers pans were highly suspect as to what uses the 'menfolk' put them to use as, thru the years,(as in drip pans for oil changes, etc) so I had zero compunction with stripping those puppies and restoring them to their former glory.
Just my 2 ¢
They came out so nice, that my Mom reclaimed her Griswold "Cornbread" skillet for further use! (Indian Giver!)