Hi, @Luis Larrubia
Thank you for posting in Microsoft Q&A forum.
Like Rahul Jindal mentioned, it's easy to use CMpivot by querying the WSUS registry, check the values in the results to see if it points to the correct WSUS server.
Registry('HKLM:\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate') | where Property == 'WUServer'
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