That’s a cheeky argument. I’ve also heard that because there are no pictures of hippies spitting on soldiers, nor references to actual events in MSM news stories, that it never happened.
Universities of the 1960s varied considerably on the political spectrum, but there was already infiltration by some extreme radical leftists. While not yet common, many schools had “radical magnet” professors, sought out by radical students.
There are somewhat easy to look up these days, because they seldom cared much for their official duties, and instead sought to stir up trouble, found radical organizations, and otherwise be pesky.
Well, if you never saw it and I never saw it why are you claiming such specific acts and words?