My brother has an Ivy degree, but he had a conservative foundation, so that helped him not get indoctrinated.
Yes. It is possible to get through and ivy League school without being infected with Alinsky-ite principles but, as you say, you must come with a solid conservative orientation. Even so, I think you learn more at a place like Hillsdale College or, if you are Catholic, Thomas Aquinas or University of Dallas. They honor Western Culture at schools like that and don’t apologize for it like they do at Harvard and Princeton.