Adding and removing data from one column to another with a button

Hey everyone - hoping for some guidance here.

I have three simple Tables. The first one records Customers and their active/completed jobs. The active jobs comes in from a (second) sales table, and the completed jobs comes in from a (third) project management document.

The sales and project management tables will be coming in from cross-doc, so what I want to do is have a button in each row that I can press to update the Customers table with the updated status of each job.

I have this working, but I am using the Concatenate and Substitute functions and I am having issues with formatting. I tried using ListCombine but it was actually harder with that.

My question is simply, a) how can I do what this example doc is already doing but with proper formatting? My current solution leaves random commas in places that don’t make sense when I move the data. b) is there a better way to do what I am trying to do?