Junior players are thrilled just to be in the SEL. No Swede would choose AHL over SEL unless their NHL team suggests/wants so. As for the obligated part, SEL clubs play to win firsthand, not to develop NHL players. Swedish clubs aren't too happy with how little compensation they get for players going overseas, either. But they will play the junior player if he improves the team.
Klefbom had a miserable offseason/preseason. I don't know if that's why he hasn't played much, but it wouldn't surprise. At the end of the day, he's never been a regular SEL player yet. He has also played 6 games with the J20 team and has only produced one assist. Give him some time to get back on track. He's got ways to go before he can be thought as an NHL player anyway, as he's both a project and was one of the youngest draftees.