Can't imagine how "multicultural competence" can reasonably be synonymous with "political correctness," which, depending on the user and the context, can now mean anything from a simple consideration of another's feelings to totalitarian cultural control.

Unless someone is trying to create a new opaque euphemism for something else through the intro of a new phrase, "m. c." can only mean competence (vague already) in many disparate cultures, an extraordinarily unlikely attainment.