Life readings "glitch"

Am I the only one that doesn't see how the life readings from the detector balls connect with everything that happened? Sure it gives a spooky element while Fifield and Millburn are trapped in the derelict, but then they put it aside as a "glitch". I mean, come on, we all thought that wouldn't be the case. However no monsters appear while in the derelict. And it can't have been the engineers life signals it detected. Janek (I think) said it started blinking every now and then but it didn't move. And David had to open the door for the detector ball so it could reach the bridge of the spaceship, and it turned around almost immediately, didn't stop for the engineer when David entered the room. David did find some green goo on the wall/keypad. Was it something lurking around, maybe watching them the whole time? Because thats something I would enjoy, watching whatever-it-was chase them through the hallways of the derelict...