Hope all goes well with the feeding, my Jag sometimes goes on fasting streaks, so I wouldn't worry too much. Although as a nice enticement, I would give the beefheart a try.
I wont worry to much about it. I have a 5.5" male Dovii in a CA community tank and he is a very picky eater. Only eat freeze dried shrimp. Any other food he just spits it out. And my 12" male jaguar is the same way.