The first film has the remaining members of the Nostromo suspect and hypothesize that the company wants it for their bioweapons division due to their experiences with it by this point. Not entirely out of the blue if you factor in the character backstories each member had, given that Dallas, Parker, and Brett are all war vets from the Torrin Prime Civil War, and the monster casually dissected them. However, they could not know for sure, this was just a hypothesis.
Burke confirms it, but also that's from his point of view as the director of the Company's Special Projects division. That makes him essentially a pretty decent sized fish in the absolutely huge company, but even with that title he was still just a junior executive. He's essentially a go-fer for the other company branches and he does a lot of bitch work for the execs. Essentially see that title as him being a prospective to become a leader in the company, but still at a mid-level position.
With that knowledge in mind, this explains why he did all this shit under the table. He was given enough power to be able to make calls himself, and he also was extremely hungry to make it to where he's a proper exec. He saw potential in the asset based on Ripley's report, and then gets good confirmation data if unintentional on this thing's abilities when he saw what the hell it did to Hadley's Hope. He wasn't just thinking of a bonus, he was seeing this thing as his ticket to getting the big chair, and possibly the job of an exec he may dislike.
The comics and spin-off shit just runs with it though since fuck thinking about this sort of thing.
