Usually the manequins are dressed to fit someone 5'7". So the shirt is already on the long side. Plus, it's an A-line, flouncy shirt. You won't get very much mileage wearing as a separate, like with just a turtleneck or blouse on top. It won't look professional enough without the jacket.
It depends on whether her current position is one where she wants to stand out. If she's just starting, she wants to fit in, right now. Show she's a professional team player. Management positions are more the stand out types.
The skirt on this one is better. It's more straight-lined. However, if you have a belly bump or pouch, it would only emphasis the problem from the side profile. But this style can be worn with separates better.