If they knew this man I dont think they knew him well like considering him a close friend.
Its hard to say what is motive could have been. It seems so many now have deep seeded rage inside for some reason or the other even for trivial reasons. Some take their own created problems in life out on innocent others making them pay when its the person's own poor choices that is at fault.
For all we know he may have been good enough to convince the security guards on duty that he was a new security guy and got in that way. I would think they would open their door because security was suppose to be tight where they lived.
He may have been the type to wail against society and those who are successful through hard work or those who seemed to be happy in life and were a happy couple. Maybe he resented what they had. So many of these kind of people seem to really detest others who are successful in life and have everything going for them. They can resent the happiness of others they see.
So his motive may have been due anti rage filled views of successfully happy people who not only had material things, but, had admiration, love, and respect from so many, but they also had deep love for each other and were planning a future together. Something this murder didn't have and knew he couldn't ever obtain it because he was the type to wallow in his pity rather than better his life. Even his reason for the bank robberies are strange as if it was okay because it was stolen from the rich banks. He seems to have a great resentment against those who work hard to achieve their goals in life. Another whiner and crybaby blaming his life on others instead of himself where it belongs, imo.
I dont think this had anything to do with drugs or drug addition. I don't think a person can have a 6 months long close relationship with someone, and never smoke, drink or do drugs not even one time during all that time if addiction was really a problem.
When the motive comes out it will be as nonsensical as other murder motives we have seen in recent years. IMO Nowadays it can be anything that sparks a murderous rage taken out on someone else through no fault of the victim/s.
He told his ex-girlfriend he was a bad man. That is probably the most truthful statement he has ever made since he cruelly and heinously ended these two victims' life in the most gruesome way he could. Maybe he was a sociopath who wanted all along to kill someone well known, and loved by so many.... showing everyone that evil can strike even in what is believed to be the most secure areas of the city.
Two beautiful lives were lost because once again evil overcame goodness the day the victims crossed paths with this monster.