Bart,

Have you tried cutting up the night crawlers? I know it's a pretty basic tip, but until I made the pieces smaller my young green Cornuta seemed scared of them / wouldn't take them. When I made them about the size of the crickets she was eating (which she hunts on her own, as she does most things except pinky move which aren't active enough) she was much more accepting, although it still takes some trying at first. Hopefully that helps!