Hm..
I have the ghost console on 2008 FSMO DC...
I might move it to a standalone machine (or another server that will be retired)
But, I dont think it's success for machines to join domain.
Why?
Well, how many DC's you got for that domain?
I have 4 DC's, and about 500 machines on ghost console.
If I do a join domain confirm to all 500, and at the same time, the DC's are replication data from 1 to another, etc, which happens by default every 15 minutes, it may get extremely busy, so if you do move console off the server, it may still cause the issue.
So, when you testing about moving the console, tell us about it when its success and working. :)