<p>You are right that he will need top grades to transfer. But that’s a good motivator to stay on top of it, even if he does not “love” the school he’s at.
If he transfers after 2nd year, only college grades will count. Transferring credits in his major could be tricky (depending on the school).
UIUC is one of the top schools for CS, relatively inexpensive, and could be not too hard to transfer to.</p>