Yes, it is she. And you have correctly identificated duchess Gedroits I think.
There is my Shakh-Bagov here (at the center), but I never thought there is Kiknadze here, too... May be, but unlikely: it looks like a summer, and he was in hospital twice and both of times in autumn.
No, if she is Varvara Vilchkovskaya, she is not my namesake, and I wonder why somebody decided that Alexei had a nanny named Antonina!