Reverse Item Merge

Merged over 3,300 items to code "Z_Discontinued" after months of working with staff to make sure all items on list were approved for merging.

Now they need 2 of the 3,300 items restored, historical data.  I created the original item numbers and setup the basic Inventory Item Maintenance information, but how can I get history back for these 2 items?  Mainly staff runs the SO Customer Sales History by Item report that shows Qty Sold and Dollars Sold amount per period, but the Item Code shows "Z_Discontinu_EA"

On Sage 100c Advanced v2017.4

I am familiar with DFDM and have a copy company before merge, but was hoping I could get back historical data for this main report in our live company so they don't have to add up history before from back up company and to current live company.