Nope, no special adapter... I have the 801 adapter fitting that came with the Protege, and the 302 is just fine with it.
I think it is probably a problem with someone getting a protege 801 adapter fitting that had the post length off on it and it needed to be adjusted. I'm vaping away on a pink 302 on my Protege right now.

Maybe it was a bad run of 302 threads? Dunno... mine are all fine.
I do recall someone had reported shorted out attys, and perhaps the 302 got blamed (which is ridiculous).
302 is a great atty. I started buying them when the RN4072 got scarce and too expensive. Joye (2 hole) and Boge(4 hole) make them (I have both). PM me if you need some sources.