A better question to ask is, why was he recused?
Trust me, if you could get to judge Contreras to ask these questions, he would refuse to answer.
“who approved the warrant “
No, I’d just want to know how much the dossier itself contributed to the decision. No justification required. They supposedly answered this question in the committee hearing, but since the hearing was classified, transcripts cannot be released.
Incidentally, keeping it to that one question won’t required a classified answer, as it is already known the dossier was part of the application.