Doesn't this encounter seem incredibly deadly for what supposed to be an introductory adventure? If the enemy uses even half-competent tactics like using compel to have a weak willed arch militant shoot himself in the head (will quite likely fail even with the +20 vs. her WP 55+30) and the servitors shooting the lightly armoured low-dodge characters like navigators with their heavy bolters or plasma cannons?
It just seems designed for TPK.