That's my husband's take on things, too. They're already manipulating him, as we've seen explicitly, so it definitely seems possible that this is another aspect of that. Especially since they know he knows who Echo is, so why on earth would they have chosen her for the mission otherwise? I'm leaning this direction myself, but they did do a thorough job of setting up a potential time for the personality to be tampered with, so I could roll either way.