3) Although Mr Lee began the process of closing the box, this was not completed and the box remained open even after he was suspended. The presumption, therefore, is that once Mr Lee relinquished his duties, one, or both of the managers worked the box (which would only be possible if they 'signed' it).
So if all assumptions are correct then Mr Lee had a genuine believe he was to be relieved for a PNB. Therefore why did he start the process of closing the box knowing that he was to be relieved ? There would be no need to close the box.
If all assumptions are to be assumed as correct then why did two Managers, capable of running the box, choose to dismiss Mr Lee and run the box, rather than relive him and run the box ?
There is ALWAYS more to the story.