Have a look in this directory: C:\ProgramData\National Instruments\Update Service\Installers
You should see a whole bunch of dated folders and inside each one is an installer and inside the 'updates' folder - there's a list of the patches/updates that were installed.
I also found a folder containing 'installation logs' here: C:\ProgramData\National Instruments\Installation Logs\Details
LabVIEW Champion, CLA, CLED, CTD
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