Dan has been sitting all by himself in the HOH for the last few minutes, mainly staring at the picture of himself and Monica. Memphis just spent a few minutes telling him that he's nuts to put him up. They can't rely on Renny, and never has a person in a two-person alliance put up their partner.
He has mentioned going against the deal, and putting up Ollie and Michelle, but he's also pointed out to himself that keeping his word will lead to everybody in the house trusting him. I'm not so sure about that.