Okay, so Glide Tables on a Free Plan.
The best option would be to use the Glide API, but that requires a Pro Plan or above.
On the Free Plan, your only option at the moment would be to add a Google Spreadsheet as a secondary data source. Then you could use the Make GSheets module to write the FileID back into the appropriate row.
As I mentioned earlier, you would need to send a RowID with your Webhook, so you can use that to search for the correct row to update.