You obviously missed the point, he won't be a medal contender unless he dramatically improves. You gotta be jumping 27ish to be a medal contender at the Olympics, and in a good Olympics 28 feet. Adoree is jumping 25 and he has maxed out his speed, and he isn't getting any taller which is a big advantage in long jump. At 5 10' , plus splitting time with football, he is not going to do anything remotely close to Olympic competition, in fact he won't even be in the top 5 in the NCAA, much less the world. The training for long jump and football are quite different, he will need to gain some weight for football, and track will require him to shave off as much upper body weight as possible. It's a pointless dream to pursue both as they are not possible for him. You gotta focus on one or the other. At 5 10' and jumping 25 feet, as impressive as that is for most athletes, unfortunately that isn't getting him anywhere near medal contention at the Olympics and his ceiling IMO is almost maxed out. Football, his ceiling is much higher, and it pays much better.
As for it's a hobby of his, i love to play soccer, video games and play basketball; i would play them all day if i could, but i had to grow up, go to college and get a job. Football or track will be his future job, and he is going to have to focus on "one" of them. He can't do both, athletes like JH couldn't do both and he was a better long jumper with a lot more potential, and he realized he had to give one up. His hobby days are over. It should be obvious if someone is giving him good advice that football is where his best opportunity to be great and make a lot of money is. Florida and LSU are straight up lying to him if they are telling him he can be a medal contender and play football at the same time. Better "track" athletes have tried to do the same in the past 20 years and no one has been able to do both at that type of level, so based on history there is no way he is going to be able to. He is a great great athlete, but he is not going to improve his LJ by 2 feet with some "coaching". When you get to the mid 20's in LJ, its a matter of diminishing returns. He is only going to see so much improvement by reshaping his body and learning some minor tweaks to his technique. His height is also a negative as far as long term potential.
It's perfectly fine for him to play both in college, that is his choice. It is a different animal if he thinks he can be a medal contender in long jump and a NFL player at the same time. The type of training and weight issues are going to cause problems for him if he wants to compete at the highest level for either one.