The first thing I tried was deleting the existing account and adding the account back with IMAP vs POP. This caused it to work better; however, deleted emails in outlook was still showing up on the iPhone.
Second attempt I turned off Exchanges caching. In outlook the emails deleted earlier that day showed up again, but iPhone and Outlook now matched. The person deleted the emails that came back and Outlook and the iPhone were now syncing.
If this doesn’t fix the problem I will attempt the “marking” as “read” tip I found on this page.
I hope this helps someone else out there…