Threat Management - Messages submitted for review still considered Phishing after review?

If you have already submitted them as false positives and nothing came out of this, all I can think of right now would be to open a support case with Microsoft to see if they can clarify why they consider these emails as high confidence phish. Something else might be going on of course, but based on what you've stated above I cannot think of any reason why they'd be marked as high confidence phishing emails.