So, interesting update to this.  After enabling the Tutor extension, the error disappeared...in one out of the two courses that wasn't working. Luckily, the one that did start working is the only one we still need, so this is not an urgent issue, but wanted to post the partial solution in case it helps others or in case there's a larger issue that the team may want to be aware of.  

I don't know the full history of the Tutor extension, but I remember the feedback popup that you get when answering questions always worked in earlier versions of the authoring tool even without the Tutor extension installed (I'm not sure a separate Tutor extension was even available in the first version of the tool we used).  The feedback popup stopped working with later updates (not exactly sure when) so we had to go back and add the Tutor extension to our courses to get the feedback working again.  

These two particular courses were created early on and have been through several upgrade cycles without being updated or rebuilt.