The headteacher appears to think he can keep this guy from getting a college education, and he might well be right.
True, there's no single gatekeeper, but there are a zillion little ones, and too large a fraction of them will stop someone without a degree, or one without a higher tier one ... and probably more in the Great Recession when there are so many credentialed unemployed.
If this guy wants to be a politician, which he seems to do, then passing thru hostile gatekeepers is his job description.
Anyway, even if he would not it's not as easy either. Imagine someone cold-calling univercities telling he's a headteached (whatever this means) and persuading not accept the student N. He'll be seen as a lunatic, wouldn't he?
That's the thing we don't know. His attitudes aren't necessarily "lunatic" based on post-WWII U.K. history, and we don't know how much this sort of thing is still an "old boys club" in which he got a hearing from people who weren't entirely cold called.
If this would be true I would not be happy with the situation in the UK. But, if he's really going to be a politician, it would be very good for him to face this thing he's supposed to fight later on.