ARE there pro bono lawers for labor law cases

Your best bet for unpaid wages is to contact the Texas Workforce Commission, Labor Law Department (not the unemployment folks) and file a "Payday Act" complaint.  This service is free. As for unpaid overtime, the TWC may also be able to help with that but, if not, the US Department of Labor, Wage and Hour Division, will pursue your and your co-employees' claims for unpaid overtime.  This service is also free.