“deputizes Mattis to march down to the DOJ/FBI with written orders to release the listed documents or face immediate firing along with a Seal Team.”
The problem with that is two-fold. First, seals cannot be used in domestic law enforcement. Marines are exempt from the posse comitatus act.
Second, a company of regular Marine infantry would be better... you do not need to negotiate movie and book rights first.
They would not be doing law enforcement and arresting people, they would be acting as security guards.