I agree that she should pump. She should use a quality double electric pump. If she doesn't have one, she can rent one. She should be pumping for about 20 minutes every 3 hours around the clock. Arrangements should be made to get the milk to the baby as often as possible.
She should also do everything she can to obtain access to her baby to breastfeed as often as possible so that the baby doesn't forget how to nurse.
Since you aren't comfortable saying why the baby was taken away, I'll add this caveat, just in case. The recommendations above are assuming that the baby wasn't taken away due to any dangerous substance that she might have been consuming. If that was the case she should certainly still pump to keep her supply up, but should consult with a medical professional to find out how long it would take for whatever it is to clear out of her system before starting to breastfeed again or before giving any of the pumped milk to her baby.