You are going to have do another one. Like yesterday. You cant keep your crabs in EE that is dry and musty smelling they will die. You need to take everything out and clean it again You should have done it as soon as the last one died there is obviously something very wrong going on in your tank for them to be dying like that. Have you tested the Humidity gauge for accuracy? Is the humidity back up? Have you discovered why everything was bone dry?