More important, he's #2 on the nuclear chain. Not of approval, but if the President gives the order to launch the Secretary of Defense confirms it is the President giving the order and passes it down the chain of command. For days a US response to a launch against of would have been delayed for who knows how long until they found him, or used an alternate identity verification method which I hope is in place. Any delay in reaction could have been costly
You seem to be apologizing for the guy.
No one knowing where he was is implausible. These folks are like royalty in that they have an army of aides and sycophants around them 24/7.