Command warning do not mindlessly trust me or others to provide safe copy paste commands, it's best to be informed about changes made to your PC before executing commands, that being said this is the method I used :
Command to grant the flatpack version of OBS permission to communicate with Avahi:
flatpak override com.obsproject.Studio --system-talk-name=org.freedesktop.Avahi
DistroAV (OBS NDI Source Plugin) GitHub:
https://github.com/DistroAV/DistroAV
Github thread detailing a similar issue with command to fix OBS' permissions:
https://github.com/DistroAV/DistroAV/...