In our GT program, all of the teachers need to have a masters in GT education or a GT endorsement. I think that there might be some wiggle room that allows them to hire someone if they are willing to commit to getting a GT endorsement within a year. Yes, it's nice to have the credential that gives you some assurance that they have at least some training but it's no guarantee of anything once they get in the classroom. One of the fully certified GT teachers (not one of my kids' teachers) was a total train wreck last year at our school. Her mid-year replacement was a young woman fresh out of school with no GT experience (long story). The replacement teacher provided a stable environment and got a lot of support from the other GT teachers. She salvaged the year for most of those kids.
I've now had three kids go through 2nd grade GT and I must say that it is one of the tougher grades for the broad range of social and emotional issues. A lot of asynchrony shines through at this age, i.e. kids who cry because they don't want be away from their parents, kids who have huge frustration because their bodies haven't caught up with their brains, kids who literally can't sit still because body and brain seem to be in constant motion. Second grade also seems to be a year when a lot of twice exceptionality gets identified. I could go on but you get the idea.
In your situation, I would be talking to the principal and asking what kind of support and training this teacher will be receiving. What kind of in-service training does your school district offer for GT teachers? Is she planning on getting her endorsement? Are there other GT teachers at the school that she can go to for guidance? Will the school psychologist be meeting with the teacher and/or the class to provide additional social/emotional support? If the principal knows what he/she is doing, they should have looked at putting some of these extra supports in place.