Hello
Thank you for your question and reaching out. I can understand you are having query\issues related to Task scheduler event data.
Please note if you can not find the event 4699(s) then it means the Task scheduler is not deleted or it was deleted by some other way.
There are Events related to this event are 4698, 4700, 4701, and 4702. The user who start the deletion can be identified by the log data.
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