Hello Swap001,
I would recommend to reset the computer data for WSUS in one of the affected WS2k19 to see if that fixes the issue. The script would be the next:
Stop-Service -Name BITS, wuauserv -Force
Remove-ItemProperty -Name AccountDomainSid, PingID, SusClientId, SusClientIDValidation -Path HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate\ -ErrorAction SilentlyContinue
Remove-Item "$env:SystemRoot\SoftwareDistribution\" -Recurse -Force -ErrorAction SilentlyContinue
Start-Service -Name BITS, wuauserv
wuauclt /resetauthorization /detectnow
(New-Object -ComObject Microsoft.Update.AutoUpdate).DetectNow()
This should fix issues as duplication or mirroring of IDs that could "confuse" the reporting.
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