Thanks for the additional information.
If it is ordinarily your employer's policy to pay, then from a legal standpoint your employer should pay, unless two things:
(1) It reserved the right to not pay for unused vacation in the event of misconduct; and
(2) You are required to give 30 days notice in order to be eligible to be paid for unused vacation, and your taking 2 weeks off during the 30 day notice period was avoidable. In other words, when you gave notice did you know that you'd need to take time before returning to work? If so, then the employer may rightfully argue that you should have waited to give the notice. But if it came as a surprise, and is not ordinarily expected after the type of surgery that you had, then you likely have a good legal argument that it was unforeseen that you'd need to take time off during the notice period, and therefore, it should not be considered misconduct, etc.
The bot***** *****ne is that if your employer refuses to pay, then you'll need to decide whether or not to sue your employer. Depending on the above, your may or may not have a strong case.
Does that answer your question? Please let me know if you need clarification, as I am happy to continue helping you until you are satisfied.