I have seen Valya's last name appear as both versions depending on source, which one is correct, does anyone know? Thanks!
Dolgorukov was his surname.
Many accounts mistakenly call him Dolgoruky/ Dolgorukii.
The Court Calendar (Pridvorny Kalendar) for 1917, p. 135, lists him as Prince V. A. Dolgoruk
ov.
In “Last Days At Tsarskoe Selo”, p. 87 (and elsewhere), his own step-father, Count P. Benckendorff, calls him V. A. Dolgoruk
ov.
The confusion may have arisen from the fact that V. A. Dolgorukov’s mother, Maria's maiden name was "Dolgoruk
aya" — i.e., she belonged to the Dolgoruk
y branch, but had married a Dolgoruk
ov.
By 1917 there were only a few Princes Dolgoruk
y left: Sergei Alexandrovich, who had been an a-d-c to the Tsar, his brother Peter Alexandrovich, Peter's daughter Olga, and perhaps their uncle, Pr. Nicholas.
The Princes Dolgoruk
ov were much more numerous.
BTW: Princess Yurievskaya was a Dolgorukova, and a distant cousin of the Pr. V. A. Dolgorukov under discussion here.