Thank you for the prompt reply & my apologies for the delayed follow-up response here.
I am indeed able to get at the full timestamp by exporting the KML file type. It’s tucked away in a “kml_timestamp_when” schema attribute that is not immediately visible as an attribute field in Google Earth or any ESRI software. I had to use ETL software to expose that particular attribute, but indeed the full timestamps are housed there.
It would be nice if the KML export feature automatically brought that timestamp to the immediate forefront as a user attribute field. It appears that it is currently buried in the metadata of the KML layer. Without the ETL software I’m not sure how I would be able to obtain the data from Avenza’s timestamp.