Had similar issue after listing a non-working older late 1970's propane tent heater at $10 and someone emailed me and said the basic same thing about a recall and it needed to be dismantled etc. I reply that I would look into it and remove the listing if needed. Found out that the company did do a recall due to some tragic fires and they were still paying $250 per unit that was sent back! I requested the recall paperwork and 23 days later had my $250 check!
Then I started searching for every unit I could find and after placing some wanted listings on Craigslist and a few other places found 3 more for a few bucks each and my brother even found another at a yard sale in Maine. Another 4 $250 checks within the next 90-100 days! This was last summer and I haven't come across any others since but I am always on the lookout for them. They tend to be found in the northeast states as that is where most of the bad units were sold over the 3-4 years. They are still backing the recall offer to this day.
I did email the person back and after finding out about the recall but it was a NON-working 30+ year old unit and thanked them for pointing out my mistake.