According to Vert, Jack disappeared years before the events of the show take place. In a flashback, Jack reported how he was trapped after entering a storm shock, captured by the Red Sark known as Tors-10 and forced to work as a slave. Jack eventually escaped for good when Tors-10 and his arena were destroyed in Gladiators.
Jack Wheeler reunited with Vert and met the Battle Force 5 six months later when they encountered him in the same Battle Zone where they battled the Vandals and Sark in Gearing Up. Though he was initially untrusting of his son's help, he soon accepted the team's assistance in finding what would be revealed to be a Red Sentient Mobi. However, it is later revealed that he cannot return to Earth with Vert and the others because Tors-10 had planted a tracking beacon on him at a molecular level and Krytus's group had picked up the signal.
In Full Revolution Jack goes to the Primordiverse via the shadow zone and collects the meta key with the intent of stopping the Karmordials from returning.Before any BF5 happened, Vert an his dad were going to have a "talk" in the Silencerz lab, or dad's work.