I got accepted to UCSD but have not completed all the pre-reqs

I recently got accepted into the UCSD chemistry program as a transfer student, but I will not be able to complete the organic chemistry pre-req before the Fall 2018 term. In my TAU, I stated that I only completed a year of general chemistry, a year of calculus-based physics, a year of calculus, and all the general education electives. I never stated in my TAU that I would be completing organic chemistry, but they accepted me and I was waitlisted by UCI (which does not have organic chemistry as a program requirement). How much does UCSD care about pre-req and should I just decline their offer now, as I am unable to complete the pre-req?
Note: I am not from a CCC

Best course of action is to give them a call and see what happens before you decline.