Modern stuff? These are homemade bombs, crafted by a couple of guys in a basement.
Anyway, I'm not going to argue with you about the technicalities of bomb disposal, because I'm not an expert on this, and neither are you. I'll just tell you that in my experience as an Israeli, it's the standard procedure. Even if it doesn't make sense, it still has nothing to do with that particular girl.
I don't have a lot to say about your theory of events either. It's just a made-up story, based on nothing more than your ignorance (for example, you seem to think that carrying anti-Israeli stickers and Arabic texts into Israel is in any way noteworthy) and prejudices.