The buck antelope I killed this year was shot in the face a day or two prior to me killing him. I didn't know it at the time I killed him, he was grazing right before my bullet hit him. I only found out after I cleaned his skull and found a good sized hole through his bone. That is honestly the best tasting antelope I have ever killed. We dont eat alot of antelope but when I grill his backstraps there isn't any leftovers.
That said I would have left that pig. No reason to risk getting sick when you have plenty of opportunities. I do the same with rabbits. If they look sick or have livers that don't look right I leave them.... general they aren't there the next day either so I know they aren't going to waste.