The college republican club should be held responsible for the damages. If they want to invite a hate monger into a campus and something like this happens, it's on them (the club should also be suspended). In addition, students, who are targeted by Milo's rhetoric should be able to bring suit not only against the college republican club but the school as well.
Freedom of Speech doesn't strip away things like Title IX federal law, and Milo has targeted women at his speeches and even caused a trans woman to leave school because she felt unsafe.
This sort of reaction should be seen as civil conversations being had and failing. Milo doesn't want to listen, his supporters don't want to listen and this seems to be the only recourse to stop this type of hate.
It's unfortunate but this 'moderate' approach hasn't lead to the decrease in literal nazism, if anything the hand sitting has given them free reign to be even more overt. If you don't have anything to add than "chat to a white supremacist" then please refrain from taking a so called moral stance that has no grounding in reality.