I hear ya DD!
Of course there will probably be things that "could have been done" - everyone can say that about any incident - every homicide, with guns or otherwise, often has things that could have been done. It's easy for us to sit and ponder on hindsight. Even with highly experience people who know in advance what to expect and the "target" (not necessarily in a gun sense!) is totally unaware - there are still things that could have been done, and always will be.
We have not met DD, only know from your posts here - so can't comment on the first bit - people do whatever under whatever circumstances - that is hard to predict unless physically on the scene and depending on whatever circumstances.
Will throw you this thought DD... It is more than clear there is a severe firearms problem in the US - not just because of this particular incident, but over a period of time. The source appears to be the availability of weapons within the public arena, coupled with a mentality to misuse them on occasion and also no consideration/vetting of individuals over time as to their mental balance/competence.
When an individual accesses a weapon or is trained in the usage of a weapon - there is no crystal ball that says this person will not abuse/kill others in the future. That is impossible to predict. That fact that they may have been trained in usage prob presents more danger to other members of the public and also to law enforcement - basically the odds are more people will get killed.
What you are now offering to do is train five people you do not know in what is described as "defensive handgun classes" with a concern to both "survive and show compassion for human beings". There is no clue as to what weapons in their possession will be used for in the future, (depending on their mental state), and this has nothing whatsoever to do with compassion for human beings. In reality, you are training potential killers and putting the lives of the public and others at risk.
I have nothing against guns in particular, even enjoyed a number of training sessions with an LE instructor friend, but elected not to possess a weapon for reasons given at the time - was more fun than anything. Basically the more guns in the public domain, the more potential killers will cause the deaths of others in the future. The public are idiots - give idiots guns and they will kill.
Think I'd be inclined to agree with your wife on this DD :-) But suspect it does not take even seeing the "multimedia show" to know this. Once again, the guy was provided with weapons when his mental state was unknown - this appears to be failure two. Failure one was that it appears the shooter had a long history of mental instability and was ignored in respect of treatment.
The "messages" left behind are not a surprise - fundamentally he was clearly mentally ill with possible delusions of persecution (tho time will tell on the reality of this). This apparently was not a new illness - it existed many years and he was a source of problems to others in "managing" him.
Only my

- would personally lay "blame" initially at a failure to get this guy treatment - there was more than enough time. Second, I'd be looking at the idiots who supplied/gave any permits/trained this young man to enable him to make his fantasies a reality.
Sure.. give condolences to the families/friends of all who were kill and injured, but no doubts this will happen again, and again. Between these outbursts, many more other will be killed (tho not CNN headlines) - simply because weapons are in the hands of the public - and again - the public are idiots and the volume of them leave little room to have some controlling mechanism
