This WebMD article may be of interest: https://www.webmd.com/fitness-exercise/repetitive-motion-injuries
There is no crystal ball for knowing exactly at which point long term damage will result from repetitive motion injury, but the longer she does the same motion that exacerbates the pain, the higher the risk of long term damage.
In the short term, she should bring this to the attention of her employer, as she may be qualify for workers compensation. In the long term, she should start looking for another position within the same company or maybe a different job altogether. It is no use making money if it puts her health at risk.