This job has to aspects to it. The main job is to take out the station's mining operation on the ground. This is so their hiring company can either merge over the operation or take control of it directly. They wish to do this as cleanly as possible to the public eye. Dr. Sir Ipk Upk decided if an outside but known force prevented mining, their hiring company could appear to take over operations either heroically or by happenstance.
The secondary job was arranged by Dr. Sir Ipk Upk to make a little extra profit outside what they were hired for. They offered nearby raiders the chance to take control of the station entirely instead of just leaching off the station's freight ships. The raiders would, of course, still have to answer to the hiring company but they'd be elevated to have legal rights within the stations hierarchy.
The players are hired to transport a large metal block from the center of the space station to the outer rim area. This throws the rotation out of balance and/or changes the rotation speed. The chaos caused by this leaves room for the raiders to come in and disrupt the military forces on the station. From there Dr. Sir Ipk Upk can convince the owning company that the station has become a liability and that their hiring company is willing to make an offer on it.