How are your other subnet users getting the application that is desired? Google play, APK?
Are you assigning the application by OG or SG? If so, are only the subnet users apart of the OG or SG?
If its a lot of users... this probably won't work below but not sure what your number is.
I would make a copy of the Launcher profile all users are current using and add the desired application to the new profile. Create a new SG & OG. Add that to all the products/apps/profiles that current users are getting besides the Launcher profile and add it to the new profile you created instead. Then switch the devices OG to the new one. This will not cause installs or re-installs by already completed products and will allow just the new Launcher profile to install while also leaving alone your other users.