I think Emma and Rumple will begin to suspect Tamara eventually. However, Tamara will probably pass Emma off as being jealous to Neal.
Rumple would be harder to get rid of than Emma but I think Tamara will exploit the difficulties in Bae’s and Rumple’s relationship to drive Rumple and Bae apart.
It’ll be nail biting to watch Emma and Rumple trying to prove to Neal that Tamara is up to no good.