If a company has a hiring policy, they shoud stick to that hiring policy to avoid any claims of discrimination.  Since you are a memeber of a protected class, then you may have a discrimination claim.  It appears their reason for not hiring you is merely pretext for some other reason.  You can file a state or federal claim for discrimination.  The Texas Human Rights Commission has a procedure that you can review online for filing a complaint.  You can also hire an attorney to help you through the process to insure that you don't accidentally waive any procedures, remedies, or timelines associated with the filing of your complaint.