That's your narrative. They had her dead to rights for both possessing and disseminating classified information, full stop. That the DOJ declined to pursue is not the same as saying she did nothing wrong.

Nor saying she did something wrong the same thing as saying she did something criminal.

There is no criminal prohibition against possessing classified information in an unsecure location. There is a criminal statute that prohibits removing classified information from a secure location - but there's no evidence that Clinton did that, since the information in question was in emails that were sent to her by other people. IOW, she received the information - she didn't remove it or disseminate it.

There's no criminal prohibition against mishandling classified information generally - there are instead specific statutes that make very specific actions involving classified information criminal. If you have clearance, don't actually remove the information yourself personally, and don't try to keep documents after the government asks for them back, it's actually very difficult to violate the criminal statutes relating to classified documents. Which again is the point you keep overlooking.

Which is why Trump could not have sic'd the DOJ on her. She didn't commit a crime. She might have broke the rules on handling classified information, but only the specific rules that are incorporated into the U.S. criminal code are prosecutable as crimes - and not all of them are.