Materials not displaying, no compilation errors. Break after engine restart.

I’ve been dealing with a very frustrating issue with the engine. Our project is running on UE5.3.2, and this is a source control project running on Perforce.

When I launch the project, some of the materials are just broken.

If I disable Nanite, far more materials break. There are no entries in the Log regarding this. The only way to temporarily fix this is to open up the material, and make a change to the material. However, this only works for that session. If the project is restarted, all of the same materials are broken again.

I have tried deleting the DDC and Intermediate folders, both the project specific ones and the ones located in AppData/Local/UnrealEngine/Common/DerivedDataCache

Any recommendations as to how I can resolve this?

I have not tested this in UE5.4 yet. We hope to upgrade our project soon, I’ll update this when I’ve had the chance to try that.