That's good that you're feeding 1/4" roaches, I just wanted to make sure they weren't too big for him. Would be a good idea to dust the roaches with the calcium, all of them for one feeding rather than the mustard greens in case he isn't eating all of the greens. For a beardie as small as yours, you should dust with calcium on 1 feeding a day for 5 days a wk and then on the other 2 days, dust the feeders with vitamins but again only on 1 feeding a day.
What are the tank temps and what type of thermometer are you using, digital strip, round gauge (dial), temperature gun or a digital with a long wire & probe end?
Unfortunately, that UVB doesn't put out a good amount of UV and can actually cause some eye issues and other health concerns. We actually don't recommend using any compact or coil UVB's. Would be a good idea to get a Repti-Sun 10.0 strip fluorescent tube or an Arcadia
UVB bulb. Both of those types give the best results in the bulb testings.
What are you using for a heat bulb?
How often have you been
bathing him? Babies can get dehydrated very quickly so that's why I'm asking.