So, my players knee-capped one of the Oeconomica Imperialis representatives and plan on putting the other one (captured by the astropath) into a void suit and plan to tie him to the ship's hull.

The weekly session ended just after the dinner with the liege, but I'd like to ask you guys opinion on the reaction from the Oeconomica Imperialis (mostly out of curiosity).

I am rolling 2 dices for taking my decision:

On the first dice I will define how badass the mafia around the gunnery stations is and how disposed (or not) they would be to massacre their own in a display of power/showing the rogue traders they are not afraid.

Second one means how important the knee-capped guy and the one tied to the ship's hull is to the Oeconomica - so they can haunt the players in the future.

Depends how powerful you want them to be, but retribution doesn't have to be immediate or even overt to the players. Whenever your ship pulls into port presumably you take on some food, supplies, people, laspacks and will be offloading payment, raw materials and dozens of other things. What if during your next shipment of food from Footfall you find out three months down the line when you finally crack them open that they've been poisoned, or have been infested with a small series of tiny void insects that eat their way out of the crates and demolish your crew's food supply.

Perhaps some of those new slaves are actually Astral Knives that begin to slowly convert and/or murder their way through your crew, meaning that next ship combat if you take too much damage the whole crew rises up in revolt.

They could also spoof your crew's identification and then go around and offend other Rogue Traders or figures of note that come to Footfall, so the next time that your crew makes port they discover that a lot of people are extremely hostile towards them - even those they thought used to be allies.

I do like the idea of showing that they're not intimidated by the Explorers, but this is the classic problem of trying to wage war on someone who has a mobile base of operations when you are stationary. The key to long-term victory is to poison the area around you against your foe, and then when they return you will have a bunch of allies to take them down. Then when your party demands answers, have them explain it's for retribution for the (named) two people they slaughtered, and just because your party doesn't remember or think they were that important doesn't mean that the Oeconomica doesn't agree.