We had one of those the other day...
Was cleaning out the hatching tray on day 25 of a hatch and was getting ready to toss a pipped egg when it started cheeping like crazy. I felt sorry for the poor guy so I finished the hatching and put it back in to finish the process.
Well, we ended up with a serious case of "sticky chick" that still had yolk covering it, had already pooped in the shell, and had a phenomenal case of pasty butt. Did the SOP with pasty butt, wiped it down as best as possible, and it's still doing fine. However, after some research, a good bath in warm water would have been much better and got it on the road to recovery much faster.
Personally, I'd get the pasty butt taken care of, get it drinking and eating ASAP. If it's sticky and not fluffing, a quick bath should do the trick.
Maybe someone else will more experience will chime in, but that's what I would do.