It soundsike the danger from that story was that she was an unwilling victim and therefore not able to giver her mind over to God. Yes I beleive that this can happen so for someone else to put you in a trance would be a bad idea because then they can suggest things to you.
The behaviour of the first person in your story is very wrong. Yes i agree that an involuntary trance brought about by someone who wants to control you is very dangerous!
The prophets were still in a trance though. I know that using drugs is not the way to do it but I do feel that if you give control over to God then the quesation must arise-who is stronger-the devil or God?