verbal vs. written contract territory dispute

Independent Salesman was offered a part-time rep for a "struggling" company--He was given a title of "regional sales manager" and a territory of all New England and upstate New York. He made a decent start "mining" the territory which clearly had not been worked by the previous rep..he was offered a salary after 4 months to give up his Independent status and work for this company full-time...meanwhile the struggling company has been bought by a group with some decent capital. Thus, some new management and some administrative shifts have occurred. His original boss is further up the line and his new "supervisor" is now telling him that all the work he did in Conn. and upstate new York actually belongs to the guy in Long Island as this was his territory from a 3 year old written contract. What is his legal recourse and should he sign the new contract that indicates not only his agreement to this territory switch, but also has a no compete clause for 18 months. does the verbal contract match the power of the written contract or not?
he loves what he is selling and enjoys many aspects of this job and does not want to leave it..
But is there a graceful way for him to indicate that he does not have to take this disrespectful treatment?
wife

You relied in their agreement with you--Based on what you say here, you could file suit against them (or at least threaten to do so) in small claims court or in regular court; filing in small claims court is easier and requires no attorney...you could try to collect all of the costs and damages that you suffered due to their behavior...