It is, but ointments more just keep the wound from drying out, so that the natural moisture of the body can do it healing process. A wet bandage would be bad, so it is really more about balance.
Yeah, I think that would be fine, just anything thick that would obscure it some. That will probably help it completely heal faster since it would help hold in the moisture a bit, too.
oh, you could also put some salve or neosporin on her spot before you put her in there. Maybe you are already? I find that makes other birds less likely to think it is something to peck at.
Yeah, it definitely happens, but I'll bet that she'll be fine after a week or so. If you are really concerned, maybe you can set up a clear enclosure for her in the moms crate so she is by herself but can see everyone, but that might be overkill. I think if you will be around to watch the...
Is her wound looking normal, too? Maybe that is the only concern is that someone would peck at it. I think that is pretty unlikely though. I would just watch closely.
I don't know a ton about hatching chicks, but from what I know about raising chicks, if she is acting normal I would get her out there. You want to make sure she imprints on mom and not someone/thing else.