Beasts in map but no Einhar

Reference Number 3.197.463.995

I just had a with Einhar mission, but Einhar did not appear. I wore the beasts down to no visible health on the health bar, but no Einhar. I could not kill the beasts (because, I assume, they cannot be killed without Einhar) so I finished the map without finishing the Einhar mission.

The map was T16 City Square, Maven witnessed (she can attest!). No scarabs used.