It'll come down to where the ERG throbbers put their votes. It's quite noticeable that in the confirmed supporters lists of supporters, the ERG throbbers are absent (JRM aside)
Do they go for one of their own in Mordor (Unity candidate my arse) or go with Johnson.
I have a sneaky feeling you are correct, they may go with Mordor but they do seem to be tactically holding back as a group. The likes of Malthouse, Cleverley, Francois, Baker, Duncan Smith et al haven't put their marker anywhere yet and you suspect they are negotiating behind the scenes