I have two young panthers and they rather catch their food. Ive been cup training them the last couple weeks but they don't eat as much out of the cup. Mine will not hand feed yet either...
7 weeks is really small. I dont think it will cup feed. I would suggest flies as they cant hide. You can also try putting feeders on the screen, if the cham is not scared of you, or try tong feeding.
Find out what she was eating with the previous owner. Also, find out how she was being fed. As mentioned, some Chams can take some time to adjust to new feeders or a new way of offering the feeders.