Chase Young had a neck procedure on 3/21 & will be ready for season; Played through neck stinger all 2023; Saints are comfortable with it

The per game roster bonus, does that mean for every game he misses, his bonus drops by a pro rated amount?

I think by guaranteed, he means that if Chase meets all of these stipulations he's guaranteed that much. Which isn't what guaranteed means. At least I've never seen it explained that way.
If it is set up like a traditional per game roster bonus, we would start the year with a cap hit of $7.52m for the roster bonus. If he plays all 17 games, we would get an additional $470k cap hit in 2024 for that 17th game. If he plays fewer than 16 games, we would get a cap credit of $470k/game in 2025.