What happened to that woman?

That 'woman' is Monique Gabrielle - and WHAT woman she is! She appears fully nude in the Tom Hanks classic 'Bachelor Party' - as well as several others! She has been in Deathstalker 2, Evil Toons, Transylvania Twist and Not Of This Earth. To answer your question, the Director of the Movie, Jim Wynorski, who was also her boyfriend at the time, stated that he was specifically hired on this movie because he was a fast worker and could deliver a finished film on a tight schedule and under budget, could re-shoot scenes without wasting any footage and more specifically, was very merciless in his editing - part of his brief was that in order for the movie to be shown repeatedly on cable, it had to be under 90 minutes, specifically between around 70 to 80 minutes (remember, B movies like Wynorski's only got a limited run on the cinemas; they were slowly being squeezed out by the major studios; VHS was glutted with product and customers were more likely to watch stuff like Die Hard than Swamp Thing as movies released by the big studios had become cheaper to rent unlike the early eighties, and were being released sooner onto video rather than six months after their initial run at the cinemas - so cable was a good revenue earner. Wynorski knew that cable (especially foreign cable outlets that could not afford to premiere the latest box office hits) would run his B movies endlessly on cable at 3 a.m. as long as he a) edited them for violence and nudity (he would add or censor scenes as per to local customs and regulations) b) The entire movie runtime including advertisements and filler for other upcoming attractions was under 2 hours. The shorter the length, the more ads they could cram into the leftover seconds, thus more ad revenue. So Wynorski's product was much sought after: it was passable B movie fare, (compared to the dreck that would follow, his movies are classics!) it was fresh at the time and the cable companies didn't have to shell out big bucks to buy his movies. So it was a win-win situation: The cable companies has something to show after their 'big' 9 p.m. premieres on Friday Nights and Wynorski had an outlet to publicize, make money off and show his movies without spending a fortune on advertising. The downside to this is that a lot of scenes wound up on the cutting room floor; that's why there is no mention of Monique's character afterwards; her part was chopped off to reduce the movie's running time.

Wynorski does shoot alternate and assorted filler scenes for his movies for foreign sales; his 1990 film 'Hard to Die' has several alternate scene not shown on U.S. Cable; the DVD has several of these scenes as extras. Hopefully, if a remastered DVD of Return of the Swamp Thing' is released with a Director's cut and commentary along with all the deleted and alternate scenes, you'll find your answer. I've just watched a European cut of the film that is about an hour and twenty three minutes; and you're right - there is no mention of her character. In all probability she was blown up along with the others when Arcane's mansion went Ka-boom, I mean, she's not as smart as she think she is, I mean, who in their right mind would actually want a lousy, thankless and dangerous job as Arcane's head of security?

We are left to assume that nobody survives the destroyed mansion. But when films have a further sequel, it always leaves room for a character to return if there is any doubt. I could have done with another film in the Swamp Thing series.