Let me tell you I have seen a lot worse in birds that did survive. But also have lost a few. I just hope you got all those maggots out and are still washing the wound each day. Not sure the neosporin is the best to use but if it's working that is what counts. I cut away dead tissue myself, but in her condition I would continue doing what you are. Your main focus at this point is keeping the flies from laying in it again. Does she still stink? One other thing I've done when girls are doing poorly is dropper feeding them pedialyte or a cheap equivalent. The kind without flavor is best, but just don't use orange or citrus flavored. If you keep her electrolytes up it will help her recover. You can also add some sugar or honey to the pedialyte to add some calories. And continue the penicillin at least until there is no sign of infection left. I don't really see any necrotized tissue there.
And in answer to your earlier question, yes birds can survive these injuries with the proper care. I wouldn't stitch or otherwise close the wound until you are sure all the infection is gone. You want to be sure it has a path to leave her body. Once all odor is gone and you see fresh healthy new tissue beginning, then you can take a needle and some cotton thread ( Not polyester ) and sew her shut. I've done it before. Just cut the thread when it looks like it is nearly healed if it doesn't break on it's own. The hole is too large for the super glue sort of binding and would just rip out due to lack of tissue so don't do that.
