Did you also enable everything in the other mac's preferences?
In Cinema 4D Team Render Client, there are also Machine>Preferences.
Make sure you also add the port at the end of the ip address, but generally Computer Name:port should work (both can be seen in the Team Render Client preferences).
So e.g. for me, I have Team Render enabled on my second computer and I connect by "secondpc:5401" as secondpc is the computer name and 5401 is the port.
Let me know if this helps,
Jan