has the ozone/cfc theory been proven?

Depends on what you would consider to be "proof."  If the standard for
proof is made high enough, it becomes difficult to prove anything.

The link between CFCs and ozone depletion is supported by very strong evidence.

I will go out on a limb and say "yes".

This is because there is a known and understood chemical reaction
between these chemicals and hence the relationship is not contended to
anywhere near the same extent as, say, the correlation between our
Carbon Dioxide emissions and global warming.

http://www.atm.ch.cam.ac.uk/tour/part1.html

http://www.epa.gov/ozone/defns.html

http://www.chemheritage.org/EducationalServices/FACES/env/readings/ant.htm