Not sure what you mean by interlaced (?). My source material is a video recorded by OBS capturing screen. BTW, I checked out now Beta version and seems like the problem is solved there. I tried to figure out what's wrong for 2 hours and looks like it was a bug...
Interlacing means that each frame of video is made up of 2 fields... and in my opinion, is a legacy format that should be avoided at all costs, bwdik... Some delivery specs require it and some shooting formats allow for it. Happy to go in details, but since you're not dealing with it, probably not necessary.
Like someone else I couldn't get this to work in 24.1. I downgraded to 24.0 and still having problems (lines in a corner pin that should easily be resolvable). But as someone suggested, putting an invert effect before and after the corner pin in the effects panel solves the issue.