New year, new softlock, ehehe -- Friend dusted off the game after RPGLB this year, and watching them made me dust it off again, so I decided to satiate some curiosity that arose this time.
It turns out that, if you don't open the chest the thief lady stops you at, at the old factory ruins in the south of the desert, and then come back for that chest after you kill her at the top of the sun tower, you just straight up soft lock the game. I suspect it's a case of "trying to call an actor that's been killed" and it hanging as a result.
I'm not expecting a fix or anything, unless you're already deciding to tinker on it, but I figured I'd report this really unlikely-to-be-triggered bug.