...Ignoring large chunks of the plot from Aliens.
Burke is the one who sent them the coordinates for the ship. He did it for himself because he wanted exclusive rights. Remember guys, when he's trying to defend himself from Ripley, he's not talking about rival corporations. He's talking about exclusive rights for himself. A big piece of the pie. As far as the company is concerned, whatever happened with the Nostromo was probably written off as a loss and the events leading up to it's loss buried by whoever at the time was interested.