Hi. I wish I had some clear advice for you, but it seems to be a tricky situation. As the previous poster said, there are risks involved. Without having a crystal ball and not knowing the people involved, it can be tough to say how they might react. From what you have said about the HR woman at the place you are temping, she does not sound exactly stable. She may not handle being given an ultimatum well. That's just my feeling due to how you have written about her in other posts.

I guess it's a matter of determining how much risk you are comfortable accepting, for a potential (but not certain) reward. Wishing you the best in figuring this out.