Cornell engineering specifically wants a recommendation from precalculus or calculus in 11th or 12th grade. Discrete math is neither.
However, since college math courses are typically one semester long, you may be able to get into multivariable calculus in the spring semester if you cannot get into it in the fall semester.
Regarding physics 2, are there any other courses that you can take (not necessarily math or science) that would not be repeats of what you have already taken?