UBT already distributes work to all available cores on your machine, so aside from distributed shader compiling it really can’t do anything the engine won’t already do for you. Last time I used it, it was considerably slower because of the time it takes for IB to spool up.
All that aside though, you’re better off spending that cash on a monster CPU like a Threadripper - it’ll be far cheaper in the long run, and on the latest TR’s you can do a full engine compile in <10 minutes on one machine.