Just to reiterate Luke is clearly being dominated and is not getting the nourishment he needs, either from food, heat or uv. He is in the most vital stage of growth in his life and living like this will create major issues for him down the line. He will be weak, highly stressed and therefore highly susceptible to infection and/or illness, parasites, etc and will struggle to fight against any possible health problems. Unfortunately they need to be separated in order for him to get the best chance in life. It's no fault of your own but leaving him this way will no doubt result in health problems and high vet bills.
Hope you can sort another viv so you can keep them both!