It doesn't take Doppio very long to think of the right wish. There's only one thing he really wants, anyway.

"I wish for the Boss to succeed."

When it's time to add his wish, he does hesitate - because that isn't quite true, is it? As much as he means what he wrote, it's not the one and only thing he wishes for--

But ultimately, this is what he asks for, after all. Even if this is just for fun... Putting his wishes to meet the Boss above their mission wouldn't feel right.