The lawsuit is nothing more than a means to pay for costs for medical and loss of pay from employment, as it would appear that they don't have a system for this within their own employment as NHL officials. OHL officials usually take out their own insurance to cover costs if this happens, but many OHL officials have primary employment where they may or may not have benefits to cover these things. I would hazard a guess that Mr Henderson does not have an insurance policy for such things, which is why he's suing.
Of course, until the lawsuit has come to its outcome, Mr Henderson has to play this to the end, where he is unable to function normally because of the hit. He's looking for an out of court settlement, which is quicker and comes with no scrutiny on him while this happens.