So, we will need a bit more information before we can help you out with a solution.
Are the buttons inside an iFrame? If so, are they on the same domain? If yes, then we should be able to track them.
If not, the best we can do is track that a user, hovered over the button.
If you email, your account manager or email@example.com, with these details, we will try and find a solution for you.