I am a Phd student in physics based simulation for Computer Graphics. I was a summer intern at WDAS and most of my colleagues were two of the following : 1) MS in CS with specialization in COmputer Graphics from places like UPenn 2) Phd in CS with specialization in Computer Graphics/Phd in Applied Mathematics from UCLA/Harvard.
The answer is right there in the article. Applied and numerical mathematicians at UCLA math department have for many years been helping out Hollywood with these problems. I'm sure their students, collaborators in other universities, etc. the academic community provides a gateway to get into this kind of work.