The key words are also "but upon probable cause, supported by Oath or affirmation."
It is unreasonable if these accountability measures are not violated and government employees remain faithful to their oath to preserve and defend the Constitution, including defending individual liberties.
If the "search" is not deemed unreasonable, then how does the rest apply?
Correction:
It is unreasonable if these accountability measures are violated or government employees violate to their oath to preserve and defend the Constitution.