Apologize in advance ... but ...
"including posting on this forum but not getting immediate response"
Yes, that's true ... no one in these forums are paid to give immediate responses. 'Free software' doesn't really mean 'free immediate support' 24/7 and responses within a time frame.
One has to ask ... how did the files/folders go missing?
Am going to assume you were following update/upgrade instructions which say to use FTP to upload files/folders of new code. FTP apps normally show a realtime log of folders/files being uploaded. Did you see any hickups there? Probably not as most folks wouldn't spend the time watching ... which is understandable. Did your FTP app give a summary at end of transfer ... something like NNNN files uploaded ... no errors ... or if there were issues with uploading some folders/files, did the summary show that info?
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Users should be encouraged to update/upgrade their moodle via git. OR Moodle should provide a way to update or upgrade core code inside Moodle itself.
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My 2 cents of course!
But ... glad you solved your problem!