I highly recommend reading the (albeit long) PDF copy of the complaint. It is not cut-and-dry like your comment makes it out to be.
According to the complaint, warnings by UCLA to not take action against the professor, were ignored. So it was not "an unfortunate situation where largely things worked the way they were supposed to".
You don’t appear to have read the complaint correctly.
He was placed on administrative leave so the university could investigate the issue — that isn’t the same as a suspension. It also completely aligns with HR's comment that “further inquiry is warranted before action can be taken.” An inquiry happened, the non-tenured professor was found to have not violated any of the guidelines and was reinstated.
The publicity surrounding his email does appear to have had an averse effect on his contracts unrelated to his post at UCLA, that is absolutely true. I’m still not seeing how him losing business opportunities because of bad publicity, caused in part by his own actions, is the university's fault. I agree with OP.
My guess is he would say UCLA crossed a line with the public response:
"So, even though a university administrator made it clear the university could not take any action against me — on the grounds that there was no known cause for taking such action — Anderson’s Dean Antonio Bernardo took matters into his own hands. He apparently reasoned that a well-timed publicity stunt might distract attention away from the school’s reputation as an inhospitable place for persons of color — to say nothing of its plummeting rankings in U.S. News and World Report and Bloomberg Businessweek.
Without any deliberation I was aware of, Bernardo suspended and banned me from campus. Then, like a well-choreographed dance, the Anderson administration started attacking my character on social media. As I documented in my legal claim, on June 3, one day after I received the first email, the Anderson School’s Twitter account sent out a message: “Respect and equality for all are core principles at UCLA Anderson. It is deeply disturbing to learn of this email, which we are investigating. We apologize to the students who received it and to all those who have been as upset and offended by it as we are ourselves.” This implied I didn’t believe in equality for all — when that was exactly what I believed and continues to believe. "
That is, if you're doing an investigation of something against internal advice, the appropriate response on twitter is nothing or something very nonspecific, like "we have no comment".
The reason for this is exactly what this lawyer is claiming.
People here are a bit glib in glazing over what constitutes potential libel or at least libel in the pragmatic sense.
Aside from the fact that a 'suspended and banned from campus' is, in and of itself an action which cause damages - the specific messaging and wording used i.e. "Deeply disturbing email" are acts of condemnation.
It's interesting that the professors Unions have not weighed in on this - why would they allow Administrators, and Students to damage profs. with these actions, without recourse?
According to the complaint, warnings by UCLA to not take action against the professor, were ignored. So it was not "an unfortunate situation where largely things worked the way they were supposed to".