Hard question to answer without seeing the busted antlers either in person or a picture. But, for the most part they can be fixed with no problems. Matching the color isn't a problem either. I just got done repairing antlers from a large Blacktail that a customer shot right through the G2 beam (2nd shot) and fractured the whole main-beam to the pedicle. It was repaired with no problem and you cant even tell, mostly to keep the structural integrity of the main beam; however we left the actual bullet hole un-repaired......GREAT conversation piece.
I agree with other two previous comments, sometimes to leave it as it was is kind of the 'whiskey in the coke', it gives it some uniqueness and flavor...plus a great story.