To add some more detail. It looks like when -clean is run as part of the packaged build script, it is cleaning up some parts of the Plugins folder, and for whatever reason it’s nuking UnrealEditor-AutoRigService.dll which then later ends up not being included in the packaged build.
I could still use pointers on how to resolve this. Unclear why MetaHuman is the only plugin experiencing these issues, and not the other plugins.