Yeah, and it seems you’ve been having the issue for a little bit here:
The master node streams out the information and coordination between the DR slaves as far as I know.
We should isolate this out from Deadline entirely. Can you start up the DR nodes the old fashioned way and run a render from the master from within the Max UI? Deadline itself doesn’t do much to interfere with V-Ray DR other than modify the config file to dynamically point to different render nodes. I think it’s worth removing Deadline from the equation and see where the slowdowns are.