Is there an example of Dinitz's algorithm running with the worst time complexity?
Dinic's algorithm runs in $O(|V|^2 \cdot |E|)$ time, so it might never make $|V|^2 \cdot |E|$ steps.
Finding a single example is insufficient, as any finite-size counterexample can be "hidden" as a constant in asymptotic notation. You will need an infinite sequence of networks of strictly increasing size with a lower time bound of $\Omega(|V|^2 \cdot |E|)$ to prove that the bound is indeed tight.