A messy case with rather suspect circumstantial evidence. Fortunately there were some independent witnesses outside of the team, including a US Marine, a number of Iraqi troops including a general. All those without any particular axe to grind have testified or provided witness statements that the alleged stabbing never happened.
I make no judgement on those who make personal errors during a dirty conflict. Somehow the USN has given immunity to a brace of accusers who have let their own standards decay well-below acceptable levels and may even have given false testimony. SAS's assessment above, born of experience, is probably on the money - one guy, falsely accused of murder, will be acquitted of the main charges and dismissed for doing exactly the same as those given immunity.
I would be surprised if we see any perjury charges down the line; the USN will just want this to all go away. Meanwhile, sending warfighters away to kill stateless, ruthless, irregular civilian combatants has become even more legally complicated, again.