E2E improve: workbook_loader()

[jadudm]

workbook_loader()

This is where exceptions will land.

That is, if there is an exception thrown (e.g. DataMigrationError or similar), this is a critical point where it should be caught, and then logged so we can come back to it.

This may be true for the general info as well (line 54).

In either case, this code has no mechanisms for catching exceptions thrown and then logging the relevant information regarding that error. We need to do so, and it is probably somewhere around here.