Oy!
my bet is that he just did not appear on any governmental radar as being a problem. what ever happen to make him do what he did was a short term change in him. the last six months. I would not be surprised if they found a brain tumor interfering with his thinking but that is just speculation.
I don’t think there is a big conspiracy. I think we will find that he spent the last serval months scoping out places then settled on Madalyn bay 32 floor.
most of the people on the intelligence agency radars are those who interact with other like minded people. I think he kept his thoughts to himself.