autodesk viewer – How to get the source file units from a backend?

We look at a way to get the units of a source file, uploaded to ACC, from a backend.

In the frontend, using the viewer, you can use various functions:

There’s also a function NOP_VEWER.model.getSourceFileUnits(), but that returns ‘undefined’ and isn’t documented.

Anyways, I’m looking for a way to get this information from the backend.
I’ve checked the manifest file, the properties (Model Derivative API, SQLite properties DB) and file and version info, but neither seems to provide this information.
Have I overlooked it?
Is there any way to get that information?
Any of the other APIs? (AEC Data Model? Data Exchange? …?)