Hi guys. I don't have any personal experience of workplace violence. In my line of work (attorney), there have been death threats from a member of the public (not a co-worker) because they received an unfavorable decision or had some other bad experience in the courtroom. In my opinion, that is not workplace violence.
I had to do a study on workplace violence years ago, but I can't remember if I actually had to do a paper. Anyway, here's my point. This is a very serious situation but it often goes undetected. If I recall, workplace violence "incidents" have several common denominators. (1) A disgruntled employee; (2) employee usually has (or had) a job with no or little control; and (3) revenge.
Now this is sticky territory and I am not sure I can explain what I am thinking in words. But, I know they mostly are disgruntled and seek revenge. Usually, they have either lost or are about to lose their job or reputation at work.
Based upon this background as a starting point, and IF (a big IF) this is the motive for the killing, this tells me that sweet Annie was compliant with his simple requests at first, until they got a little bit over the top. One article said her responses were "conciliatory." Ok, if that is to be believed, she succumbed "nicely" and complied with his requests. This gave him a belief that he had control, which is what he probably sought his whole life. After all, the requests seemed reasonable to Annie.
As we all know, when this happens, some folks can take this to the next level. It happens at home, work, at the grocery store. When you give a little, people want more. It tells me she likely got to the point where he was really becoming more of a nuisance than anything else. She may have made some comments to the other animal techs like, "What's up with that dude Ray? He's so obsessed!" Or maybe she said, "If he doesn't back off, I am telling Dr. Bennett" type of thing. Perhaps not knowing the person she made the comments to were his family members (or perhaps not) and they discussed it over beers and dinner.
My point is that IF this was WV, then he was disgruntled and sought revenge. Those are usually the common denominators in these cases. Most of the time, they have already lost their jobs or just lost it. Perhaps he "perceived" that his job was going to be in jeopardy soon.
These are serious things and usually there are not really warning signs.