Explored some more and got some feedback for everyone (still working out the kinks but figured I should report back). I am currently using VB Virtual Cable which allows to connect virtual sources. I selected the virtual cable on the audio out field in the NDI Watcher Beta and then selected the same virtual cable in the live inputs. This allowed me to bring the audio from the individual NDI sources to the live inputs in Isadora. Still a few kinks (the separation between the various sources is tenuous because of audio feedback and the responsiveness of the connection requires a couple of restarts) but definitely a work around!