Strange issues happening within replies to comments via email

Hi all,

I have several executives that don't like having to log into workfront to respond to update threads, so I shared with them that they can just reply to the email notification of the update via outlook.  It will add the comment to the thread for them.  But recently I have run into 2 issues:

Issue 1: for the last 4 months or so, their messages have also included text strings like this after their response - how do I get it to stop doing that?: 

Issue 2 is much more problematic

Today someone posted a response within a chain.  One of the people tagged in the update recieved this in their email:

But this is what the rest of us saw both in our email and within the update thread in WF