ORDER IT !!!!

actually, you will not sacrifice other food option. in F, your veggie meal is loaded ADDITIONALLY. you still have all choices from the menu. usually, you get three different appetizers (plus caviar) in F (one vegetarian), and thus, you even get a choice of three more. so you then have a choice of four veg appetizers.
for the main course, you can nearly bet it will be some kind of pasta if you order western vegetarian food. it will be OK, but maybe the selection of the menu is nicer, so you can still choose it.

You have nothing to loose. So if you are two in F, order one western vegetarian and one indian vegetarian meal and you will be fine.

Flight attendants like this because in the end there are more F class main course choices left for them