McAfee Email protection and Web Protection are not directly on the DXL yet and can therefore not take advantage of enterprise reputations set in TIE.
But they all integrate with ATD. So for example if TIE submitted an unknown file to ATD for analysis and Email or Web protection would then later on send the same file, ATD would already have it on the blacklist.
Somewhat of a follow up. Does the MEG send the file information to TIE, or does ATD? We are seeing an issue where ATD alerts us on a bad file (from MEG) but that file is not in TIE, so we are not clear on who actually sends it into TIE.
I had the same question than you and could not find any option in MEG that allow it to join TIE through DXL. I have also looked into the documentation of MEG, DXL and TIE and I didn't find anything related. I guess that as MEG is going to be discontinued McAfee is not going to develop the integration with TIE/DXL.
So answering your question, it is actually ATD the one connecting to TIE.