Using World Composition, navmesh is broken on play unless any sub-level is manually loaded in-editor first

I am using static navmesh generation with tiled landscapes using World Composition. I believe I have everything set up correctly. I have nine sub-levels each with its own nav mesh bounds volume overlapping the playable space.I also have a single navmesh bounds volume in the persistent level, which has been posted frequently as a workaround for navmesh issues involving World Composition.

If I play in editor with at least one sub-level manually loaded, everything appears to work perfectly. AI can move around the world, and the navmesh streams in and out with the sub-levels. The problem is that if I play without first manually loading any sub-level in the levels panel (does not matter which one) the navmesh appears broken, only appearing as thin strips on the edges of some tiles and completely missing on others. Is there any way I can solve this?

Thanks for your time.