from what i have read frill dragons need to be in a room or area where they cannot see any other lizards. this stresses them out and they get temperamental. it seems like this is what is happening with yours. maybe the reason he/she wasnt doing well to begin with is the parasites. i think you should put him/her back to where he/she was before. (cant rem. gender) by moving him to the room with your other lizards you might be adding stress to the parasitic infection. try giving him a treat with tweezers so he warms up to you again and sees you mean no harm. good luck.
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1.0.0 arg. b/w tegu
1.1.0 white's tree frog- popeye, jack
0.1.0 southern painted turtle- ms.tortle
0.1.0 crested gecko- crimson
1.0.0 pinto hedgehog- dante