They arrive in system, riding on the rogue trader. Once arriving in system, there are multiple broadcasts from different commanders and generals, as well as the inquisition. They are all basically asserting authority for various reasons about why the other people should either stand down or follow orders.
It seems like General Aicken has made himself unavailable, and so is not able to be relieved of command or consulted, per se, and so there are two parallel chains of command vying for control of the situation.
They try to find a way to resolve the situation, to delay them before the inquisition can depose enough captains of the ships to get the votes to rescind the general order to stand down. The only way they can think of it to make a public declaration of excommunicating the acolytes, so they can give the captains of the ships an excuse for why they are going to publicly refuse to cooperate with the acolytes. The ships controlled by the guard then begin to broadcast that they are not allowing the acolyte ships to board them.
They try to head to the planet to stop the plan, and stop the psyker there from collecting the souls. The acolyte in charge by the ships transmits to them, it seems she is also a high level administratum, and can completely accurately lay out all of the problems with their claim, and why their claim is void based on their inquisitor being already excommunicated. They ignore her and move on to the planet.
The ships controlled by the inquisition begin to chase after them, though one stops eventually. The other cruiser begins to send out smaller shuttles to chase after them. The party lands their shuttle near the location of the psyker. They make a broadcast to the guard below to clear a path, in order to not block inquisition business. They drop down in the half track, speed over to the psyker’s transport, blast it open with a plasma blast, revealing a psyker in a tube. Priss pulls out wiggleforth, and boils that psyker in the tube with a full blast of her strongest fuel.