For roughly six months his wife, Sheila, watched her husband's personality change drastically. He had become distant. Suspecting an affair she hired a private investigator to have him followed, but two days into the operation he gave her her money back and, frightened, suggested that she drop the entire matter. When he asked that she return the photos he had given her she refused.
Working under Baal, who had recently come to Earth and landed in the middle of big business, Jameson was ordered to report to the closed Farrow-Marshall factory in Edison, Virginia. His purposes there are unknown, though it may have had something to do with sensitive data regarding Baal's cloning practices. While there, Gerak's First Prime Yat'Yir dispatched forces to capture Baal, and obtained Jameson instead.
Jameson was taken back to Dakara where the Goa'uld was beaten and prodded (with a Goa'uld pain stick) for information regarding Baal's present whereabouts. He eventually revealed multiple locations for the Jaffa to search.
Jameson and the Goa'uld within were likely disposed of when Gerak obtained the information he needed, eventually capturing Baal (rather, one of his clones) and executing him in front of the Jaffa High Council.
Ex Deus Machina - Jameson, taken as a Goa'uld host, is snatched from Earth by Gerak's forces and eventually reveals the locations of Baal's hideouts.