It's weird, the chunks WERE getting marked as static before, but after tinkering with them, they no longer are. Chances are that I must have done that while tinkering with things. I'm now able to move the prefabs around, and it's working quite nicely.
As for not committing changes, it's the only way that I can get prefabs containing tilemaps to actually have mesh data. I had to play around to figure out the proper steps to get it working right: To get it to work I drag the prefab I'm working with into a scene, commit the changes (this will add the mesh data and make the map visible), hit edit, and then apply the changes to the prefab. If I just commit the changes and apply to the prefab, my mesh data will be empty in the mesh filter and mesh collider when instantiating the prefab.
I feel like I'm exploting some bug, which is a bit worrisome, but it's working so far...