Both are words best used to describe someone else than oneself or an action taken by another.

When it comes to that Peyton, I wouldn't say genius if it's his throwing skills, but maybe his insight into to who to throw for is. Genius instead of intelligent because it's a real heat of the moment kind of action I would presume.

So it's more about the local context and time it is said. Something everyone would say is stupid like bonking your head on a table till you pass out 'because you think your head feel funny', might be a future genius move when you're researched in the hospital and discover a brain tumor.

Genius is in the extreme more geared to something crazy and Intelligence more to something nicely thought out (or being able to think up a well thought out plan on the spot, like a good jamming session, the plans follows are you try to figure it out almost naturally).