Only trying to help here....
Your boas look to have ok weight, but the cage set up would be more concern. The carpeting mat will dry things out alot. Try cypress mulch in both setups for a while. Put a hide box in cage at one end...your cage being so small for the bci, you can make a hide box out of wood just leave the sides off where it would louch the sides of glass. Put some sort of paper or better yet...the hard foam construction insulation around the back and one half the front. Make sure your heat stays at 90-95 hot side and your cool temps 82-84, no less, except maybe 79 at night on cool side but keep hot side at 90 . Anything less than these may lead to respiratory infections(RI's). Keep humidity at 60-75% daily. It will naturally drop due to heating temps, so misting frequently is a must.
That may not be a pretty cage when you are done but the boas will be happy. That is why most use a melamine cage or a boaphile cage type. For years I used the glass aquariums, and have been very happy since building my own from melamine. Hope this helps...just my 2 cents. Andy