I take it you're a mod but not a dev? You had me hopeful for a moment. I updated from 1.31.732 to 1.32.740. My 1080 Ti is still being reported as having 3071MB. If it looks like a duck & quacks like a duck, it is a duck. This is a very old bug & it isn't hard to track down or fix such issues (the cause is obviously down to an overflow as somewhere an assumption is being made that gfx memory won't report such a large value).
If you're not in a position to help actually fix the issue please feed back to the developer that the issue exists & won't fix itself.