Spot on, RAT 5. This decision is indeed a violation of ICAO Annex 13.
Just Culture and the terms of Annex 13 exist for a good reason, i.e. that they save people's lives by enhancing aviation safety and thus preventing disasters.
Anything that goes against Just Culture therefore threatens safety. Consequently, that Judge's decision not only is in breach of an International Convention which his State is a signatory to, it also jeopardises aviation safety.
He should be prosecuted under criminal law on the grounds of endangering other people's lives.
Annex 13 being part of ICAO and the UN is nothing more than a collection of agreements among states. Not all parts are accepted by all states. Most notably any state has the right to take exception to some parts with due notice. It is common for a state to modify their exacting participation by inserting exceptions under the laws of the state. Such exceptions typically give the state's courts the right to make exceptions to annex 13 to serve the interests of that state.
That appears to be exactly what is at the bottom of the rulling in this thread subject