Wrong cast!

The cast listing for this movie is woefully inaccurate. Not only is villain Bertram Hammonds (?) not listed, but half the characters listed are from the first film, not this one, McArdle in particular. Why did they do this? Were they honestly so lazy they just copied and pasted the entire cast list from the first one without regard to who was in the sequel and who wasn't...?

And this isn't a mistake on IMDB's part. They're just listing what was on the film's end credits. I just watched it and it's exactly like as described, with the first movie's cast right down to no-names like "Porter" and "Policeman" and Hammonds and his drilling crew completely MIA.