looks like the laserdisc wasn't full-frame either

That's what I was wondering too. According to IMDb, the second film had an aspect ratio of 1.85:1. As far as I could tell by sizing the frame from that laserdisc image, it has a ratio of 1.74:1.

But what's odd is that the screenshot of the DVD release does have a ratio of 1.85:1.

My thought is that perhaps both were framed wrong. That the laserdisc wasn't cropped enough and that the DVD was cropped too high. I believe that the extra information is on the film when they capture it, but they crop it down for the theatrical release. That's how sometimes in the theaters you'll see the boom mic at the top of the screen. If I'm wrong, then I'm not sure how to explain it.