Joint custody is joint custody. With teenagers, the Courts let the kids stay with whichever parent they want to, regardless of who is 'primary' custodian. The Courts will not make a teenager go to a parents house they don't want to go to in this situation. Like it or not, that's the precedent here in Oklahoma, as verified by multiple attorneys here.
"Always go straight forward, and if you meet the devil, cut him in two and go between the pieces." - William Sturgis, clipper ship captain, 1830's.