I have wondered that, but as far as I'm aware he has no other problems. From the reading I've been doing, some say there is no link between red feathering and liver disease, but it is the internet and there are so many contradictory things said.
I think it may be the illness as the wing feathers are also deformed, but will wait and see what he looks like when he arrives. I would assume if the liver is causing his feathers to go red he would also be jaundiced, but that's just me thinking it, no info on it at all.
If you have any experience at all, let me know.:wave: