We could try the following method to see if the peoblem is solved.
Delete the contents of c:\windows\system32\grouppolicy
Run gpedit.msc remotely via psexec - this thankfully runs silently so the user isn't aware. gpedit.msc recreates the structure under the grouppolicy directory excl. registry.pol
From there, run an updates scan cycle, which recreates registry.pol and gets updates working again.
Here is the similar post about this WUA Group Policy:
https://www.reddit.com/r/SCCM/comments/iv0uf6/unable_to_read_existing_wua_group_policy_object/
Note: Non-Microsoft link, just for the reference.
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