plot holes can be character decisions if they make absolutely no sense at all, but the scene with the worm creature made sense. They had no idea it was some deadly creature that could break through their suits and burrow into their bodies. I mean a firefighter goes into a burning building to save people, he knows the dangers, he could be killed, but he made the decision to try and save people. Same with this, this could be a friendly creature or could be a killing machine, they didn't know, its not that hard to believe they were curious what it was. Its not really suspension of any disbelief...If you can't handle that decision then like I said, almost every sci-fi movie has that same thing happen. Someone always makes a wrong decision and they die because of it in every sci-fi, fantasy, horror, and really almost every movie.