I certainly hope someone else is holding Rocket Ranger Girl's helmet for her and she is holding somebody else's for some odd reason, cause the one she has won't fit her head, unless it is made of latex. Even then it is an awfully tight fit and she'd probably be unable to look out through the viewports. Doesn't do much, protection-wise as well, since with such a tight fit it is either just paper thin sheet metal, or it has no padding inside whatsoever.
But at least she won't get shot easily. The other guy's gun is missing three very critical components on his MP5: Cocking lever, ejection port and magazine release. So he won't start shooting any time soon, couldn't fire more than a single shot if he could and could not reload his gun once he is through the first magazine.