...which seem to only make use of pdflatex and sphinx-build, but please correct me if I'm wrong.
> Deleting it (obviously not the ideal solution) resolves the error and > allows the files to be built as expected.
I"m confused about what you deleted, exactly?
The file that's throwing the error - tablespace_dialog.rst.
> Are these actual bugs or am I missing some kind of dependency?
I'm guessing a dependency issue, but I don't know what it is exactly. My experience with building these docs on Red Hat-based systems is that if you install the "authoring and publishing" package set you're good. I never tried to narrow down exactly what you need from that.
I have all of these installed already (and more) trying to figure it out, unfortunately.