SCCM (W10 1809) update hung/failed now missing from Software Center

We have been pushing the W10-1809 update through SCCM to the clients, most have worked flawlessly, but those that have failed generally are no longer advertised in Software Center.  Not as failed, not as installing, not as available. It is just not there. 

The computers are in a dynamic device collection; those that have fully completed the upgrade sequence, are removed from the device collection.  These failed computers continue to show in the device collection, but fail to show the update in Software Center after the update hung and therefore failed.

How can I get the updates to show in Software Center again? 

I've deleted the cache, tried renaming the C:\Windows\SoftwareDistribution and C:\Windows\System32\catroot2 folders.  I can't seem to find much help elsewhere on the internet.