There is nothing wrong with what you are doing here. This is exactly what I would do had I access to a vet. You are taking advice from some smart people. You are getting her to an expert. This is the best anyone can do.Unfortunately I rarely anticipate the worst & have ended up with very sick chooks because of it.This time I thought I'd be a little more proactive.
I can't seem to call it right. No doubt something that comes with experience ~ & I don't have a lot of that.
Please try to have confidence in yourself. You are doing fine and she will be OK.