We don't know whether the rosalio still seals Moka's power or not.
Maybe that cute smile was the key of the happenings
Just think about it, now Moka is cold but still has the cute side that Outer Moka used to have, and maybe that's why the rosalio's that effect doesn't work anymore but it doesn't mean that it doesn't seal her power. If that's the matter, Moka doesn't need the rosalio anymore. (however I don't think the real reason why Moka needed the rosailo is to live with humans because then she wouldn't attracted to it that much)
If someone wants back the rosalio that rather would be Tsukune (and the other girls of cource
) than Moka..