Oh I’m sorry!
The paths need to be fed as "dir 1" "dir 2" - which makes sense since the point of quotes is to account for whitespace, and whitespace is also the separator. This way it runs without issues and skips over errors. Thanks for the pointers.
Edit: Follow-up question: Is there a way to use the --use-fs-snapshot flag without running the elevated terminal? I thought placing the exe into System32 was supposed to achieve that.