That stock looks to be too long for her, and the forearm is too short. She's having to get her support side arm straight out too much, she needs to be able to get that elbow under the gun more to be able to hold it up/control it better.
I'd bet she would be a lot happier with something like a 12.5 - 13" LOP conventional style stock (hard to say without being there) with a premium recoil pad (wood is easier to cut down and fit a pad to), and a 'field' length forearm as opposed to a short LE length forearm. The less weight out in front of the support hand the better, too.
And once you got used to a shotgun set up that way, I'd bet you'd like it better too... I know I do. My wife is 5'4", I'm 6'3" and we shoot the same shotguns...