Do we have any recourse in a verbal agreement

My son had a verbal agreement with a contractor working for a cable company. His many attempts to get the manager to sign a written contract were met with resistance and this manager telling him that he wanted to bring him on as an employee, even though the original agreement was for him to be a subcontractor from his own landscaping business. Last week, while I was in the hospital, my son was picked up on a warrant charge and was unable to contact this contractor for the week he was in jail. Today when he was finally able to contact the contractor about his pay which should have been deposited on Friday last week and wasn't. Their verbal agreement was that they would pay him $60.50 per job, in addition the company would be responsible for paying his gas to and from the city the job was in which is 78 miles from our home. The first day of work they assigned him to training at $150/day which was not part of the agreement, then when he told the contractor he needed money for gas the contractor changed the agreement again and told him it would come out of his check for the week. Currently with all the deductions the contractor has taken and what we have recorded as my son's work this contractor owes him a total of $1,195.50, if we charge him mileage that would be $300 more. My question is how can we get this contractor to comply and pay what he owes him and if he refuses what is our recourse since this was a verbal contract and we are in Texas? We believe he has text messages between him and the contractor sending him to different locations to perform the job he verbally contracted him to do.