Maybe one of the antitheft cable systems used for laptops could work? Would require a little custom drilling of the holes and etc. Or replace a couple of the screws with anti-theft TORX type ones. Regular phillips heads can’t work on them, nor bondhus ball driver heads, but the special screws cost quite a bit, and you can still pick up a kit of various drivers at some place like harbor Freight.
But if this was me needing to do this, I’d use a couple of the security screws (just to slow them down and make them think twice) plus tape across the joints… the same kind of tape you see used for warranty stickers, that shows tampering if removed… used to have a lot of that used for rental VHS tapes at the local stores… maybe Markertek still has it?
You might also consider using disposable stick-on “g-shock meters” to expensive gear like decks. These are often used in shipping, and are calibrated in various amounts of shock. Putting one in a visible spot is like parking a spare police car along the road where speeders travel: it makes people a little more careful.
If I were sneaky, I’d have a second one hidden inside the casing, rated to a higher g-limit, to help prove who was careful and who wasn’t. Extra clause in the rental paperwork says if the g-shock is busted, you’re paying extra for a maintenance check and re-alignment, plus any damage.