I would just be careful when pulling the deal id into the other tabs. If you ever sort a sheet or delete a row, then it will break the relation to the other sheets. I would recommend a script to copy new deal id’s in TabA to the other tabs, or make the user first create records in TabB, TabC, TabD using a form button from the the TabA details in the sheet.
Then I would use vlookups or query or something like that to join the sheets together in TabE instead of blindly joining row by row.