Hi - a few pointers for you. First those weights are OK for 9 month old dragons although the lighter one is a little underweight. Secondly, dragons do not like change and will often stop eating for up to 10 days at times so I wouldn't be worrying yet and the tongue and digging are more likely exploration habits than anything else. At this age they will soon be looking at mating/forming territory so separating them before either mating or fighting occurs is a must otherwise you could be in trouble.
Can you post a photo of your set up and tell us a little about it - temps, type of lighting and heating etc. as we may be able to help fine tune it a little.
Beardies from an Australian point of view.