Honestly- they’re probably interested in her themselves.
BUT too immature to communicate with her themselves.
If this is a real life scenario it’s difficult for Tina. If she approaches them (if she’s interested in 1 of them) it could backfire for her.
If they (or 1 of them) like her it’s a scary thing for them. The game they’re playing is to save face and blend in with their peers and mates.
Teenager boys are more mature away from other boys (in practice away from school).