|Hi Music Guy, have you inspected the floppies?|
Fully open the slide, then turn by hand and see how the recording surface looks.
Compare against a known good one.
Would think smoke damage alone would not effect the recording surface, only the outside of the floppy. Possibly such that such that the slide is not opening properly when the floppy is placed in the drive.
Please advise back on progress.
Good Luck - Keep us posted.