In this quote, should it be ensure or ensures?
Comprehensive experience in all aspects of entertainment and media law in combination with exceptional people and project management skills ensures excellence at every level.
I believe it is ensure.
While longer, you are essentially saying [A] and [B] ensure [C].
For easier understanding, the sentence can be re-written as:
... experience ... ensure(s) excellence... in combination with ... people ... and ... skill ...
Since the subject is "experience", the verb must be in singular: "ensures".
However, the original sentence is definitely not a model on how to use English properly. While correct, it is difficult to understand. Until you have enough words to have a meaning, one already forgets the beginning.