Chaps I think you will find that the no tow advice relates to the fact that parts of the gearbox are internally lubricated by a first motion shaft (input shaft) driven oil pump. This is driven by the engine even when in neutral so with a none running engine there is no oil pump.
This can cause considerable damage but please don’t panic, it’s not towing the car from one side of the road to the other or onto a slide back recovery vehicle (I have heard owners panic over this). I can’t quote a safe distance but certainly a few yards is okay being towed to a motorway service area is not kind of thing.
Hope that helps.
BR
Colin
