Sorry you are having problems with the copy on BCL, I did just test the GitHub copy and that appears to work and can be found here https://github.com/NREL/openstudio-common-measures-gem/tree/develop/lib/measures/air_wall_zone_mixing

Here is screenshot

You could also consider the new Air Boundary Construction object in OpenStudio, which supports new EnergyPlus air wall capability. That is shown below.

I did just get it updated on BCL so it should match GitHub. So you can try to update your local BCL copy instead of using GitHub.