Indeed. If it were me GMing? That guy you killed was the governor's relative. Now you're having trouble getting an audience because he's in mourning, and the local cops are looking for a murderer. If you're lucky, they'll ask you to help, as agents of the wider Imperium. If you're unlucky, then you're suspicious outsiders and you'll get the blame. That's ignoring the possibility that the local government is part of this cabal, in which case you'll be chained to an altar and Pink Horrors will be nibbling on your extremities.
Don't expect any help from your Inquisitor because he's light-years away and you'll have been hanged by the time he even hears about it. You're too junior to be worth doing anything retributive over, too. Off to the gallows; I hope someone has good upper-body strength and a high Toughness.
If the
GM thinks it was disruptive behaviour, that is. If everyone's fine with it, fair play. However, from your description, there's some disagreement. You really should make sure all the players are on the same wavelength, or you'll end up with some friction in the group.
If it were me? We'd have listened to the ranting, to see if he said anything that tied in with the mission briefing (you know, the stuff on the ship that you skipped?

), and possibly staked the place out and followed him. We'd have met our contact, but not necesarily mentioned the madman (hey, this contact could be in on it too). Then, once we'd found out there was a group of cultists meeting in town, we'd probably have attempted to infiltrate their hideout ad gun them down.