Thank you for the post, it is very valuable , however I see one minor issue here. It will work if update has been installed and Windows have been boot and while inside the Windows environment it is able to send a diagnose report , however consider the case where update affect the Network Driver or Reporting Mechanism so no report will be sent or the update caused failure in booting of the operating system where no report will be sent too.
In this case we are in state where systems are not reporting and it might be valid like user turn off their device or they are not connected to the internet or there is network connection issue (internet failure and so on) or it could be a failure like update failure. I am wondering is there any solution for such scenarios too or we should leave it to the expertise of the administrator to identify whether not reporting status of the update is due to failure or update installed successfully with no issue and there is only a connectivity problem.