I'd have bet my house on it although now you say about the MIS/PBP matter I'm not so sure!
I guess the other thing that clouds the issue is that with the BIker Scout, for example, it's possible to find a MIM card with the LL figure-correct dark grey LL blaster OR with the lighter grey Kenner blaster. I guess you could therefore argue that product was being mixed up at that stage so why not figures, too?
I had always believed that MIM cards and figures were packaged in Mexico. Mainly because of the small hole in the back of the card behind he figure: they wouldn't do that in the US otherwise why not do that for all MOCs packaged there and there's no evidence of regular Kenner MOCs having that hole, only MIM. In my assumption they'd been packaged in Mexico I believed they'd only be packaging their own figures not Far East ones.
Hadn't considered this all before so great question, Chris. Guess we'll have to wait for someone with actual knowledge to come along and answer it!