A brief update before our trip:
We communicated with Cookie. I communicated what I want and expect of him and he said that he wants that also. Hooray for communication! He was/is worried that he is expendable since I already have Vanilla and that he should try to find a primary also and not rely exclusively on me, but doesn't believe there is a better match out there for him. And he's mainly scared of being left alone, if/when I realize I don't need him anymore.
Vanilla is much relieved now that she feels her problem is not with poly but with this particular metamour.
Me: bi female in my twenties