What to do about this new employer?

Definitely call back! But if the test expires, its not your fault b/c the DM told you to call, and she didn't answer or call back. She is responsible for making sure you get a new one. She is probably very busy doing something. I'm sure everything will work out. I say, don't call more than 3 times and leave at least one message (but not 3). Good luck to your GF!