If she gets a lunch break, what she can do is eat lunch quickly, then go out and take a 20-30 minute walk. If she doesn't get much of a lunch break, as long as it's safe, she can pace the deli counter. a lot of people may pace when they get anxious or nervous. I'll pace a small area when I'm stuck at an airport waiting for my flight. it beats sitting in a chair for hours. If the airport is large, I'll walk to the different terminals (as long as I don't have to pass a security point).
If a person can't get in any exercise during work, that means they need to do what they can before or after work. that's what a lot of members do. I don't workout during my lunch hour. I eat at my desk. LOL. so I do get in a morning workout.
If she needs to drive to work, she can park at the far end of the lot and walk the extra way. take the stairs instead of an elevator or escalator when possible.
I think pacing the counter area is her best bet as long as it's safe.