I actually kinda think the opposite.
Like you said, the getaway was flawed, but it does seem to be decently planned out - that plus the use of a silencer (which I believe decreases the “performance” of a gun in some ways?) suggests that getting away was as important as ensuring the target was dead.
I don’t know what this is, but I’m leaning away from it being a disgruntled patient/family member.
I should probably jump ahead and read some more posts before commenting, but I’ll comment anyway.
First, I’d love to know what “threats” he had been receiving. Were they from one person, one group or multiple people not particularly connected to a specific group? What were the threats - physical harm to him and/or family or other executives at United? Or were they threats of being publicly “outed” for some type of real or imagined “transgression” or offense? I doubt they were threats of legal action since someone that would threaten legal action is not IMO likely to execute another person like this. Did he make any changes to his personal life/routine to try to ensure his safety?
As far as this person being a “wronged” patient or parent of a patient - This could be the case, but there are several other possible motives here, too. The somewhat sloppy method of disguise & get-away and a public attack clearly in an area that would have cameras could mean the shooter is very angry & in despair/grief and feels like they have nothing to lose, however the fact that he/she even attempts to disguise and get-away makes me feel like he doesn’t really want to get caught or die but that he would be OK if that happened as long as he accomplished his mission.
I don’t think this person is going to kill themselves for the reasons in the previous paragraph. However, if it was a “revenge” killing for treatment denied that may have resulted in the death of a loved one, he could end up killing himself when he realizes executing his target didn’t bring him any sense of peace or justice.
Having been through a lot of issues over the last few years with our medical insurance provider, I can say that it is VERY frustrating and exhausting to have to constantly battle for coverage that you pay for, especially when you feel that someone with no medical knowledge and/or human compassion is sitting behind a desk making arbitrary decisions based on the “company dollar” that can profoundly and tragically affect your life. This could be by denying care/coverage which could result in worsening health or death, but it can also lead to devastating financial consequences that could result in you losing your home, retirement, etc.
I’m not saying that this is what happened here, but if the shooter is someone that feels they lost “everything” while a company executive continues to live a wealthy lifestyle, I can see that anger festering and finally exploding. To be clear, I am not saying this is in anyway justified, rather I’m just trying to think from the shooter’s possible mindset.
For example, a girl that went to school with my kids was diagnosed with cancer in Middle School. Her family had insurance but so much of her care wasn’t covered or fully covered and the bills (medical, household, etc) mount while the parents are least able to devote time to working their job(s). They ended up losing their home, getting divorced, etc. Fortunately the girl is cancer-free and has since graduated High School, but the toll on these families is devastating.