Has he always been a poor student or is this something new. Poor grades don't always equate to laziness or a learning disorder. Personal issues, peer issues, alcohol, drugs, or even some form of abuse can lead to poor grades. Perhaps a few sessions with a therapist can shed further light on the subject.
My own son, a 7th grader, is a prime example. He's been an honor roll student all of his life and takes all advanced placement courses. But his grades this year have been terrible. If not for taking weighted AP courses he probably would not be eligible to play this season. I won't go into details other than saying that for some kids the teen years can be emotionally hard for any number of reasons and sometimes seeking someone to talk to outside of family and school can be a great benefit.
As for the player you mentioned, if "none of the above" in these posts fit and he can't afford travel ball there may be American Legion baseball in your area.
As for Latin American ball, it's not much different than sports in poor neighborhoods in the U.S. where education is undervalued because sports as seen as a quick fix to money woes. And from what I've read exploitation of baseball players is rampant in those countries. That being said, showcases here in the U.S. - with all of the money and costs involved - are our version of player (and paying parent) exploitation.