If they are both not wanting to eat and are not housed together, and that's the only symptom/issue going on, could it be something wrong with your food stick? I'm assuming they are eating from the same batch of live insects and/or greens, veggies, etc.
I only mention this because a while ago I bought a batch of 1,000 superworms, as I always had from the same breeder, and I also buy a large batch of BSFL as their main staple feeder...Both my female and my younger male stopped eating their bugs all together, and neither of them are a lot of greens anyway because they were both too young. I honestly didn't realize what was going on because it happened slowly and started first with my male and then my female. Once I realized this was a problem that was not just a quick fluke and both had stopped eating all together, I checked everything, their lights, temps, etc. They are in totally separate rooms, so the only thing they have in common is food. Well I had forgotten to change the oat bran/oatmeal in the superworm bin one week, and when I went to do it the following week the smell of ammonia hit me in the face as soon as I opened the bin up. It was nasty, and then I remembered that I hadn't changed it the prior week because I wasn't off the day I usually do it. So I went and bought a new bin and put in fresh oat bran/bedding and then moved all the superworms over to the new bin, and only fed them the BSFL for the next few days, which they still refused to eat for about 2-3 days after that. I ended up using the blender to mix up a slurry of greens, Calcium, multivitamin, Pedialyte, etc. and I had to force feed them only one day, then the next day they both at a few BSFL, and gradually they went back to normal, but it took a while before they would touch any superworms. So either the superworms actually made them both sick, or just the smell upset them enough that it caused a problem. I've never forgotten to change the bins again, but it only took that to stop them both from eating.
Since their food is probably the only thing your 2 dragons have in common, that might be it.