Hi,
Sorry to hear this.
And everything seemed to be going so well. Wild caught lizards can be a nightmare to work with and any stressors can tip them over the edge if they haven't settled and got some reserves behind them.
I have seen the stress of a move from bad conditions to perfect conditions cause an animal to go back before they de-stress and start to get the benefit of the new environment.
The fact she was eating well for you kind of argues against this to me though - would be intrested to see what the necropsy comes back with.
Don't let this discourage you though as you have come so far already.
dr del