The ad_group_criterion_history (ad_group_criterion) has a field for ad_group_criterion_display_name that populates the name for custom audiences, provides an ID that can be joined to user_interest table for display names beginning with (uservertical) but does not provide a lookup table for other audience types such as demographic.  

Google mentions this in this support case regarding a seperate API pull from detailed_demographic which is not available via FiveTran. https://groups.google.com/g/adwords-api/c/zrGG6yykyUw/m/2CkT65kcEgAJ

I would like to request that we have the detail_demographic be made available for us.