Well I spoke to Sebastian who is the software development manager at Maxon and he said that xRefs have been fixed in C4D which I suspected and am over joyed about 🙂
Also I got it slightly only on the Redshift licencing front I only have to buy another Redshift licence to get Team Render working full blast rather than another C4D or Maxon One subscription so that works out even better.
Lastly I have also found that turning off CPU in the Compute Devices in the Redshift preferences on the Mac speeds up rendering a fraction too - happy about this. But dedicated GPUs are still gonna be faster in Redshift than any of the current Macs. I was hoping Apple where going to be releasing an M4 Studio this month but alas no… I guess I will have to repair my ailing PC at some point LOL.
GazzaMataz's post in Team Renderer Using Redshift & Xrefs was marked as the answer