Do not speak with this facility. Contact a qualified personal injury attorney asap. Do not be intimidated by the "waiver". Waivers are not legal; in this circumstance. It is a ploy to try to intimidate you into believing that you cannot sue (or as I would say, protect your child). The fact that businesses are allowed to have people sign these rags is repugnant. All the best to you and your son.
Your question suggests that your attorney is acting properly. Schedule a meeting and have your questions/concerns answered. Gallager, Bassett is a third-party administration. They are not looking to help you.