I think it has to be accepted that what that person will do in your absence will be far less than what you are capable of doing – essentially they are providing an emergency service. We had a similar situation and one of my colleagues put together a “front end” so the temporary person has a reduced access password which brings up this screen where they then click on certain boxes eg. LSTF, LSTS, DIPM etc. The front end has text descriptions of the buttons so is as un-tchnical as it can be. I suspect that approach with a short operational note would give a good starting point.
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