I was one week early, but I'm still going to say i called it.
Perhaps this was the wrong time to tell him, but I think it was going to be necessary at some point for the four alpha males to know about all the hidden idols in order to be able to collaborate on their situation.
All four of them agree that they are going to be targeted after the merge and they don't have the votes to do anything about it, So the only thing that I can think of, is that one of guys that holds a hidden idol needs to win individual immunity and then they use all three idols they have to make sure that vote is so split up that their four votes determine the outcome.
This probably all breaks down if one of the guys that doesn't hold a hidden idol wins immunity since it's unlikely anyone will give up an idol in order to force the others into guessing who's not holding.
What they really need to do is tell everyone that they'll be drawing straws to see who gets to use the idols. Even if they don't actually do it, it might create enough confusion that their four votes would be the determining factor.
Of course, this only buys them one week, I don't know what they can do after that.
And I have to hand it to Phil, that was about as classy an exit as I think can be made on Survivor, by taking one for the alliance by telling everyone to stick to the original voting plan and that if he ended up getting eliminated it was worth it to force the idols to be played.