I heard some kind of rumor about a fandub of this game on some... cassette tapes? if it's true, geez, it's gotta be old. Regardless, I was interested if anyone knew anything?

Hm, I've never heard of that. Especially on cassette. Maybe there's an English dub of the anime but that's the closest I've ever head of.

This is kind of a stretch, but you might be thinking of the Snatcher radio drama that Kojima produced with Suda51, it would not surprise me if that somehow wound up on a cassette tape. Haha.

In any case, if you do manage to find whatever it is, definitely post a link because I am very curious.