Make sure your nephew would actually be happy at the university even if he chose to deviate from engineering (and therefore, I think, this 3+2 plan). If he is interested in playing college athletics as you say, that probably goes a long way. But being academically happy is also important.
I say this as someone who was also interested in engineering and also has the technical chops (I'm a mathematician now); it is different from any type of science or math you find in high school and it is really difficult to gauge if it will be a good fit. It was a horrible fit for me, and I gave it up after my first semester. Talking to actual engineers in various disciplines would be a concrete and productive way to overcome this.
But King's College is supposed to be pretty nice. At least the choir sounds good at Christmas.
that my answer was sufficiently absurd to make that clear.
over these last 5-6 months. I'm certainly certain I can't appreciate it anymore.