Correct. It's better if there have been no babies in the group you're moving her to for a few weeks but as long as there aren't any babies when you introduce her it should be OK.
Again, there WILL be fighting. There is a dominant female in every group and, when you add a new female, there will be some jockeying for position. Keep an eye on them to make sure it doesn't get too serious but you'll have to let them go at it for a bit.