Yea I'm pretty sure both Yaron Brook and Onkar Ghate had separate speeches shut down when they mentioned to a conservative audience that immigration isn't an issue.
Also remember that conservative speakers are going to liberal colleges, no one is trying going to conservative colleges where you could get expelled for being a homosexual. Of course conservative colleges have zero alternative viewpoints so there's no one there to invite non-conservaive speakers which would lead to many a shut down speech I imagine.