The ZR300 on the Euclid lacks an ASIC chip that the ZR309 Developer Kit camera has, and this missing chip is software simulated in a fork of Librealsense. Attempting to use the main Librealsense in the Euclid will result in the fisheye camera not working.
I do understand your concern about the form and the problems it presents, as other developers have commented on it.
I was attempting to use the euclid fork on the Euclid. It turns out the issue was that I had somehow got my Euclid into a messed up state where the euclid-camera-access package was no longer present. Reinstalling it from the iso corrected the issue.
Glad you were able to fix it! Thanks for letting us know