I don't think that would work well for Github and similar applications. FINALE seems to work (haven't tried it yet) by running a LabVIEW VI (in LabVIEW obviously) to generate HTML documentation from a VI or VI hierarchy. This is then massaged into a format that their special WebApp can handle to view the different elements. Github certainly isn't going to install LabVIEW on their servers in order to run this tool.
They might (very unlikely) use Python code created by Mefistoles and published here to try to scan project repositories to see if they contain LabVIEW files. But why would they bother with that? LabVIEW is not like it is going to be the next big hype in programming ever. What happened with Python is pretty unique and definitely not going to happen for LabVIEW. There never was a chance for that and NI's stance to not seek international standardization didn't help that, but I doubt they could have garnered enough wide spread support for this even if they had seriously wanted to. Not even if they had gotten HP to join the bandwagon, which would have been as likely as the devil going to church 😀.