In those few minutes of conversation, Mouse discovered many things he didn't know, such as the fact that the "Navy" was not the only force operating in human systems, especially in the outer rim in the mining areas, it was the stations themselves that hired mercenaries to explore and "pacify" certain areas or planets that could have a mining interest.
The business consisted of having the rights to exploit the conquered area before other colonies. As chance would have it, the current captain of that mercenary cruiser had been a comrade-in-arms in the authentic Gundam navy during his years of service, that and the fact that he needed an engineer specialized in spaceships and weapons made it a better and cheaper option than hiring the services of the station.