If they knew there was something specific there and that it was definitely hostile and they really, really wanted it, they would've sent a properly equipped team. We know this, because it's exactly what they did the one time they explicitly knew about the Alien and went to get it -- Alien3.
Everything in the movie speaks to them knowing "something" is there, but not what; that they'd like "it", and that they're okay if it goes south so long as it comes back.