Anything involving this will be handled by gov't lawyers, not by him, and you can bet if he does end up in front of the court, his responses will be 100% coached by those lawyers.
His attitude outside of court is admissible to court. It likely would be brought up to show that the agency did not represent the consumer in good faith.
Federal court cases have already been influenced by the current administration's actions (speeches, interviews, tweets) outside of court documents and statements by attorney. What Pai says now can indeed be referenced within court proceedings. Whether that will be effective or not is unclear.
The court system seems to be looking the other way with this current administration though, so I wouldn't get your hopes up too high that his actions would have any effect on any court case.
Bureaucrats don't serve the public. They serve their institution to implement policy. Policy which is ambiguous. If any lawmakers cared they would have clarified this through law.
Anything involving this will be handled by gov't lawyers, not by him, and you can bet if he does end up in front of the court, his responses will be 100% coached by those lawyers.