Unless a minimum sentence is required by statute, it's very likely that he'll end up with probation if 1) this is truly his first time to run afoul of the law, 2) he did complete the rehab program, and 3) the judge/jury decides that he has learned a lesson from his injuries.
In fact, even if there is a mandatory minimum sentence, if he has a lawyer, cooperates with the DA, and avoided saying something really incriminating when the detectives interviewed him, he could very likely plead guilty to a lesser charge and ensure probation. This is most likely what will happen. (IANAL disclaimer)
As far as "justice" and "morality" go, in this instance, justice was done. The perpetrator broke into a house with a firearm and threatened people. Regardless of his motivations, the scoundrelous nature of his victims, or other historic perceived injustices, in this moment, he was at fault and guilty. He could have - and perhaps should have - lost his life. He should be grateful that he didn't die instead of being angry at others for his current predicament.
If the homeowner is involved in everything you say, then that is for the police to handle. The perpetrator wasn't there as a vigilante to exact justice. Most of the time in life, somebody's actions will catch up with them, whether through the proper channels or not. They often reap the consequences of what they sow. If your portrayals of the homeowner and family are accurate, their day will most likely come.
Still, there is no guarantee of actual justice in this life. That comes afterward. If you hope for true justice, which we all deserve, then don't place your hope in man.
Hebrews 9:27 "And inasmuch as it is appointed for men to die once and after this comes judgment,"
(FWIW: I live just up the street in Keller but hadn't heard much of this story on the local news.)
