The only thing in the project that description might fit were some niagra systems. I deleted those from the project’s file structure and reloaded the project. Same crash when opening the level.
As of this morning, I have gotten the project to a stable place by deleting elements from the nested blueprint actor in reverse chronological order. Once the level opened up without issue, I added back in everything except the most recently deleted object. Still fine. I add back in that one object, and the same crash pops up. So it seems to be something to do with a specific Kitbash3D model. This makes no sense to me whatsoever given the error I’d been getting, as the model’s blueprint has no moving parts or sims in it.
Perplexing, but stable for now. Thanks for your response!