How to get iTunes to recognize iOS backup transferred from another computer

I made the dumb decision of transferring my iOS data to a new PC and get a new iPad at the same time. I backed up my iPad to the old PC, wiped the iPad clean, then got new iPad. The intention was to sync the iPad to the old PC and restore from that backup. However, the new iPad pro has USB-C connectors (I don't have an adaptor that will work), which my new PC does have. So, I transferred the backup files from Appdata/Apple Computer/...etc (the folder with a thousand alphanumeric characters in it).

I've done a search on here, and everything tells me how to copy the iOS backup from one machine to another, but none of them tell me how to get iTunes, installed on a new PC, to actually *recognize* the existence of this backup so I can restore to my new iPad. All instructions that I've found on here (such as this one: https://support.apple.com/en-us/HT204215 ) assume that when I click the Devices tab in iTunes, I actually see the backup. But, as iTunes itself is a new install, it's blank. How do I un-blank it?