he isn't hitting...do search, get him in the cage, make sure he is hitting everything between 15 and 25 degree launch angles, use your protractor to document results...have you checked the local show case circuit? get him in front D1 recruiters before he turns 12...if he is gonna make the MLB by 18 you are in jeopardy of falling behind schedule!!
Or you could try playing whiffle ball with him in the backyard between practice sessions, making him laugh while you are playing and falling in love with the game itself...have a bunch of his buddies over for all afternoon homerun derbies and whiffle games and burgers when you are finished!! give special bonus runs for bat flip creativity!!
To close to call!!
on a serious note, underhand soft toss off a bucket is great and don't be afraid to throw from knee if you feel you have to throw overhand. T work is underrated, most young kids don't do it...most older kids do it every day...