I really hate to defend this guy because he clearly sucks. But honestly: smart move. Your phone password and much of the contents of your phone should be considered speech and you shouldn’t be compelled to testify against yourself. That said, if this phone was government property then he shouldn’t have been the only one capable of unlocking it, which is a policy failure.
You’re right, the satanic temple has never been successful at eliminating religious favor from government policy by overtly using religious law to do something shocking.