There is nothing miraculous about this "washing" (умив, umiv) with fire. In fact, it is so transparent cultist and pagan it is embarrassing and damaging.
There is plenty of evidence that the fire is lit from the hidden icon lamps and that it can be 'created' with white phosphorous ex nihilo. In all cases, the "miracle" is an insulting fraud.
personally i don’t know that’d i’d get behind it unconditionally but i’m not about to call the patriarchs involed perpetrators of fraud.
i think it’s compeltely possible that its a miracle and i’d hope and expect if someone in the church had evidence to the contrary they’d either stop the ceremony or come forward with the truth.