Is a contract enforceable under NY law if it's unclear, or ambiguous?

Generally, the answer to this question is no, although there are some exceptions, such as where other evidence leads to only one interpretation of this contract clause.

Since the answer to this question is almost inherently a fact-specific issue, if you aren't sure whether your contract is ambiguous, I would strongly advise you to contact a New York lawyer whose practice focuses on breach of contract cases.