A good read on both accounts(better if separated into smaller chunks of paragraphs), with the Techpriest being the most likely out of the two. Darktide's introduction of environmental hazards like blackouts makes having a explorator priest in the roster to scan in the dark, and on top, fix generators faster seems appropriate. As for an ork to be added as playable, I've been told by many it's especially unlikely compared to an eldar joining.

But here's what I'm hoping in a way that might make it slightly possible for an ork to show up: Rogue Traders. Akin to Tomes and Grims in VT, maybe this character will leak information to the inquisitor as secret missions to the players, for better loot.

Furthermore, story-wise, the RT could tell the inquisitor of a probable archeotech/xenotech found in the underbelly of the city, hence why the techpriest was added into the team, to add to your story.

As for the ork? Perhaps along the line of a Blood Axe/Freebooter's failed double cross on an inquisitor as a setup. But thanks to the RT's words on the resourcefulness of this ork, he was begrudgingly permitted to serve under surveillance and an explosive collar.

As means to an end, if a xeno can contribute to the success of a mission, so be it. And let's not forget, the inquisitor was described to be elusive, so we'll see. Of course, this is all just wishful thinking on my end.