No they are not carnivorous. They will hide and then come out at night and find any salad that may still be in the cage, or escape. But they wont hurt you dragon.
I feed Blaze his dubias in a bowl. He's a shy eater so I just dust them then dump them in and walk away. When Blaze was smaller I had a small bowl and the dubias would climb on top of each other and get out into the viv. When I cleaned the viv I would find a dozen or more under the tiles in the viv. Now that Blaze is bigger (16") he has a deeper bowl and they can't get out but when they did they never bothered him.
I love dubias as a feeder. They don't stink so that is a major plus for me.
How are they not carnivorous? Don't say things that are false. I've given beef and chicken. Dog food, cat food. Fish flakes. Etc. all of that has meat. They will not bite though, that is true, they are way to shy.