I've had a couple timescrops filled till squeakers regurgitated, something slashed n or poked hole in.. never ill effectscept mess of warm wet fermented feed.
just find parent that has young not too much smaller, and stuff that one under when crop empty, maybe pour vinager down crop to stop whatever from happened, and just check morn and again at night. it works. lol
if it doesn't or they shun it, its gonna be weak n possibly in pain and can die anytime anyway after stop babying it, or other pigeons want to chase away amd may kill it later. I've had happen twice after heat snap hatch, and heard of many many times. better than spending on one who may have short miserably painful life, and spend betterment/rescue of others from now on.
horrible thought, but some jus roll craps as layed and hatch.
splayed leg i just stopped prob in white racer, as had splayed legs, n i just massaged and flexed backwards and prob good in couple days.