This morning we attempted to massage the egg along which stimulated Aquila to push the egg out eventually. She seemed better and had gone to sleep to rest, but later she was found pressed up against the food bowl dead. When we checked her, her breastbone was visual, and it appeared there might have been a second egg inside her.
Egg binding is a common way for female birds to die. So far Florence has been egg bound twice and survived, and Aquila had been egg bound a few months ago (where the egg ruptured internally) and survived. For details on egg binding in finches, how to prevent it and help those who are egg bound, see: http://www.finchniche.com/features_eggbinding.php.