@mikepence doesn't look like there's been any further action on that (I'm not aware of there being an issue filed on the OSD repository about this). I know @msalsbery is currently slammed with other projects. Did you try the workaround mentioned? If you don't need to support pointer events (i.e. not mouse, not touch, but the Microsoft pen), maybe that's good enough?
Anyway, if you want to help push it forward, you can file an issue on the OSD side
Also, depending on what you're using Fabric for, you could also switch to the SVG or Canvas overlay, but then you'd have to build your own interaction code.