I’ll need to look at the API more, if I can retrieve the record via the Glide API with some filter conditions then I could match the comment with the airtable record id and pull the row id that way… off I go to read the API docs!
Edit - there is no GET request 
Oh well - the only other way is to not sync the admin comments or make them invisible or store them on another table, and push them out via the API.
Seems like a big workaround however! Might just be quicker to bring the admin side of portal build forward and into Glide!