Can't Validate, Cook, or Package. Source/Runtime errors

Hey all, I’m having an issue with UE4 4.20 where I cannot Validate, Cook, or package my project without getting an error relating to the source/runtime folder. The engine will tell me the error is related to grass node and landscapes, however if I remove the grass node from my material I get a different error and both come from the source/runtime folder. Cooking or packaging will fail, validation will simply crash the engine.

I have tried deleting my save, intermediate, binaries, etc and regenerating the package to no avail. I have also tried loading up the project in a non source build of UE4 and still get the same error. I thought maybe this had to do with world comp and some landscape proxy still being reference so I deleted the map and it’s tiles and cleaned everything. That didn’t work either. I have no idea what is throwing the error as the engine is not pointing to any particular asset. I have included the logs. Here is a screenshot of the error as well.

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