VNAV
Well, A VNAV Approach might be fairly safe nowadays, however it only is considered a NON precision approach with the minima accordingly. With your normal CAT I ILS being 200' ceiling and between 800 and 550 m RVR, the nonprecision deals with minima around 450 to 800 ' ceiling and around 1,5 km visiblity. It always depends on the particular approach published. And given the weather, it simply might not have been an option. I don't know, I wasn't in that plane...
Nic