You fight the fights you can win and let the ones you can't go. That seems unsatisfying, and it is. Mark's personality changes took up a lot of air time, so it's worth talking about why that might be happening. With the proviso that we really don't know how the brain works, trauma, growth, and swelling can all produce significant changes in personality, affect, and intelligence. Very, very difficult to determine an exact cause.
Families freak out all the time, and paramedics are trained to deal with that , too.
EMS is for the living and those who have a hope of living, not the dead. That sounds harsher than it's meant to, but really, it's the way the system works, and it's the way the system should work. I rather doubt it. If this is the definition of cognitive impairment, I think I'd better pull myself off clinical duties and not ever touch a patient again, because I'm like that pretty much all of the time. Yep, he's pretty clearly cognitively impaired.