I've never been to the Hoover Dam before and I'm on For the Republic Pt2. and I can't find her anywhere in the whole damn (pun hehe) place. Bug? Or does she hang out somewhere beside her office?

She's either in her office or a little supply closet with a desk. The other room is down the corridor and to the right of her big office.

If you were instructed to see her by another NPC, then there will be a quest marker for her.
In addition to the office, I also found her in the nearby hallways and at the top of the stairs in the big room off the main generator area. (The one that is accessible from the visitors center main desk area.)

I have to talk to her to start a quest. I will look for her in the generator area. Thanks.