RE Shader warmup bug? HHALP!

We are exporting builds for playtesting and noticed something strange, we have a shader warmup that happens before the main menu. This prevents stuttering as we insatiate a bunch of scenes and nodes with shaders in gameplay. This works, creates the .cache file inside the vulkan folder in app data.

however, the game doesn't seem to be able to read from it the first time the game is launched from a clean install. both mac and pc. closing and restarting the client fixes the issue.

When running with the exported console we can see this error (only when running for the first time off a clean install)

[mvk-error] VK_INCOMPLETE: Error writing pipeline cache data: Failed to write 4 bytes to output stream! Wrote 0

We are discussing a screen after the shader warmup that instructs users to restart the game... but that feels crazy. We've tried messing with a bunch of settings in the export and no luck. Version 4.6.1. Using both official export templates and ones we've compiled from source, same issue. Doesn't matter if we export from editor or headless build.

Has anyone dealt with this?