Trait is nice, but it is not magical remedy that gives Mathilde supernatural skills in related tasks. As it is, she never worked with Ulthar. She never debriefed scouts/soldiers. She never tried to put together picture of what is happening in twisting multilevel undeground caves, as opposed on flat surface. There is racial disconnect. There are possible to overcome but still present issues with language.We have a trait that specifically gives us bonuses in this situation, though. And we've worked with scouts and soldiers before, in the Invasion of Sylvania. And we've been sitting around Dwarven Scouts for at least weeks now, and happen to be standing right next to another Dwarf who's well-versed in both cultures and can help correct any misconceptions, should they crop up.
Sure we have a trait. But all that trait does is give Mathilde a boost to such actions. It does not make all above issues go away.