Assume given a pullback square of simplicial categories $$\begin{array}[c]{ccc} A&{\rightarrow}&B\\ \downarrow&&\downarrow\\ C&{\rightarrow}&D. \end{array}$$ Suppose further that one of the induced arrows $Ho (B) \to Ho(D)$ or $Ho(C) \to Ho(D)$ is an isofibration, and for each couple of objects $x,y \in A$, the induced pullback square of simplicial mapping spaces (I abuse the notation by writing $x,y$ instead of their images in $B,C,D$) $$\begin{array}[c]{ccc} A(x,y)&{\rightarrow}&B(x,y)\\ \downarrow&&\downarrow\\ C(x,y)&{\rightarrow}&D(x,y) \end{array}$$ is a homotopy pullback. Does this imply that the original square is in fact a homotopy pullback of simplicial categories?