I would put the baggie right under the cluster. I don't know your location but in my location packages have starved with the feed on the opposite side of the follower. Sometimes the bees just don't know how to find the syrup if it gets cold when it is just outside their reach. Make sure it is good and warm and have enough of the syrup outside of the baggie that will lead them to the source. There is no reason they shouldn't be taking it.