Hi Michael,
You would still import your data same as always, all I'm suggesting you change is how the data is transmitted out of Quick Base to your external service. Essentially the AddRecord call will only catch a single record change when multiple records are added. The ImportFromCSV call would only be a change in your webhook, it essentially would change the webhook to let it know to capture and pass out each record added via an import to your external service. It just happens to format that as a CSV file.
Alternatively, it is possible to write a script that is more robust then the webhooks, as the issue with webhooks is they fire once off of those actions taking place. So that single Add Record happens on Record 1 and finished, while CSV will scoop up all the records you add.
