I've never seen any evidence that Nasty Ladies part 2 was released. In fact, all of the Part 1s I've seen for sale over the years have been punch-outs. Part 1 obviously didn't sell very well if every copy ended up in the bargain bins.
There are countless examples of adult titles being released out of sequence, or with volumes missing.
Swedish Erotica #39 (1981) [I0022] and
Swedish Erotica #52 (1984) [I0025] were released, yet none of the other volumes appeared on Laserdisc. How random is that?
Even some of the story-based adult films were released seemingly at random. For example,
Things Change: Letting Go [AVIV-0035] is the sequel to
Things Change: My First Time and the story follows on from the first film. AFAIK, My First Time was never released on Laserdisc.