I am Back on a real keyboard
We suffered from this Problem a few years back along with 15 People working concurrently on a file. In the past we didnt found a convincing solution and focused on short time merging (mostly manually later with ETL Tool. Strategy was to send isolated, unique edited packages to a merger end. But dreamed from better solution. Nowadays a saw a good progress on the online, 356, Ondrive functionalities, close to solve this.
I dont want to bore you with stories from the old time, but the task is not easy one, fully working out of the box by 24/7. However isolating the uniques and merging could be an approach. Are there any relationships between the entered columns e.g. formulas etc?