The vocabulary word that best fits the sentence "I had that this guy was going to be a danger to us" is "presentiments."
In this sentence, "presentiments" refers to a strong feeling or intuition that something bad or dangerous is about to happen. It conveys the sense of foreboding or apprehension that the speaker has about the person in question.
The word "bedlam" means chaos or uproar, which doesn't fit the context of the sentence. "Corrugation" refers to a type of folding or ridging, which is unrelated to the speaker's feeling. "Specters" are ghosts or apparitions and "impotence" refers to a lack of power or effectiveness, neither of which capture the idea of a premonition or forewarning.
On the other hand, "presentiments" directly aligns with the speaker's sense of unease and foreboding regarding the individual, indicating a premonition or feeling that this person poses a danger.
In conclusion, "presentiments" is the most suitable vocabulary word for this sentence because it accurately conveys the speaker's apprehension and intuitive sense of impending danger.