Multivariable calculus is calculus 3, but if it is not a college course, it may not be transferable for subject credit.
Disagree with the blanket policy of not claiming the credit.
Claim the credit if allowed and either
A. It can fulfill subject requirements but is not an important prerequisite for something else, or
B. You try the college’s final exams and know the material well.
Premed is a special case; if you claim AP credit for premed courses, medical schools still want you to take courses in that subject, though more advanced courses can work.