Bus Incident Legal Recourse

My son told his bus driver that he had to use the bathroom and it was an emergency while they were at the highschool in his district picking up more students. She refused to let him off to use the bathroom. He ended up pooping his pants shortly after. She then let him off at the elementary school to clean up. An adult at this school escorted him but no one offered him a change of clothes or attempted to contact me. He could not do much to clean himself without new clothes and had to sit in the mess for an hour long bus ride. He was made to sit in the very back and no one was allowed to sit in any seat directly next to him. Other students took recordings and posted it on a student group chat on Snapchat. This was humiliating for my son. I still have not been contacted about the incident

Indiana