The mercs do not turn off their chest-lamps till they see Steve approaching them from the lighted half of the moon, so he would have seen the small distant points of man-made light in the darkness ahead and known that something was up; the moon was supposed to be deserted.
On more than one occasion, Rudy reminds Steve that his bionics cannot function in extreme cold. So how, while Steve was trapped in the sub-zero chamber with his defective spacesuit letting the cold air in, was he able to use his bionics to force himself out of there?
The cryogenic testing chamber would have a virtually unbreakable substance like Lexan or safety glass for its door-window, not just obviously-brittle ordinary window-glass that shatters in huge jagged dangerous pointed shards.
Steve's "space helmet" is obviously just a cheesy "bubble-hooded spaceman" prop --- it's a simple roundish hard-plastic hood with a clear plastic swivel-down face-shield that's just loosely attached at its rear ends by two simple pivots on the sides of his helmet; it's not even an air-tight seal. Real space-helmets are usually massive blocky-shaped units that attach to the rest of the suit to form a continuous bulky cumbersome cocoon.