Although it's unfortunate that ICAO hadn't taken more of a leadership role in TCAS operation, history has now provided ample proof that all pilots need to be on the same page for TCAS to be an effective tool. I feel Mr. Nielson was also a victim in this terrible tragedy, any ACC facility that allows a controller to man two positions as outlined should be held responsible.
If they didn't have the money to properly staff the facility, I hope that the judge sends them a strong message as to how much it costs to improperly staff the facility.