@hek
Thank you! It looks like it's working.
The relay is now talking directly to the GW. The 2 right-side temp sensors however, are now using the relay node as a repeater :P
I can live with that (still working as designed) only thing now, is that I think I have a faulty wirering connection to the radio on the relay node. After a while it goes "offline", but the fun part is that if I powercycle it, it's back online.