In general I'd look at using a Conditional Split to divide up your collated dataset by campaign. Though I haven't done so myself, there are plenty of articles on...

Yuck. Ugly. It's a little tough to diagnose the specific problems you're having without the code for your scripts/regex.

You've got no consistency either within records or across records...

I've been in your shoes. Consider leveraging your previous career to gain a position that will allow you to interact with and use SQL Server in an employment setting....

Dohan has it correct: The UPC algorithm is that the check digit is the number that needs to be *added* to the weighted sums to equal the next higher...