Have you checked with a Workers Comp attorney yet?

Take the comment from the Work Comp company about sending their nurse to you appointment as a warning.

You need good legal advice.

Work Comp is supposed to be a No Fault system but the insurance companies look at the injured worker as the enemy. Their goal is to pay for as little as possible, regardless of your true needs.

You sound like you do not want to be adversarial but you need to be. If you don't, they will take advantage of you. You paid into the Workers Comp system with your 15 years of paychecks. You are due a good result. You are not going after your employer. You are up against an insurance company. They don't care how long you have been employed.

Pride will not pay the bills when your Work Comp benefits get cut off. Hard work will not overcome a brain injury. You need to get legal help so they can protect you and your families interests.