Taking her to the kidding pen to early will stress her. Actually, birthing outside is usually cleaner than inside, no matter how clean a pen. So, if she should successfully kid outside, things should be fine. You do not have a buck in with your herd, do you?
Looks like she’s getting closer. I’m guessing either tonight or tomorrow night. You don’t have to, but if you want to you can clip the hair around her tail and udder so that the blood and other stuff from birth is easier to wash out.