That's so annoying James - not what you want when you're on holiday. I'd also be fuming if it happened to me.
Difficult to provide an opinion without a picture of the damaged area. How large is the area of damage and whereabouts on the door is it? What colour is your car? If the damage is small and in a fairly inconspicuous area, i think I'd try and touch it in first. If you're not happy with the results, then you could investigate other options when you get back to the UK. A light metallic colour may be more difficult to get a good inconspicuous result with a touch up pen, as it sometimes looks a different shade, but it depends on size and location of the damage.