Tip injuries are fairly common. One of the things you can do if the ears are still being posted is to tape the ear with the injured tip up almost to the tip and use a band aid over the tip of the ear (to protect it) that way you can inspect the tip as often as you need to and simply replace the tip, medicate or whatever until the tip fully heals.
When I had an older dog with a tip injury it turned out the the cartilage at the tip had been damaged and there wasn't enough uninjured skin at the tip for it to heal normally. We ended up doing a little minor surgery--under anesthesia the vet removed the cartilage at the very tip, debrided the skin so there was clean tissue and put in two tiny sutures and I posted that ear--without taping all the way to the end and used a band aid per above. When the tip healed we removed the sutures and that ear was maybe 1/4 or 3/8 of an inch shorter than the other ear but really wasn't noticeable.
Hopefully you won't have to do that.
dobebug
When I had an older dog with a tip injury it turned out the the cartilage at the tip had been damaged and there wasn't enough uninjured skin at the tip for it to heal normally. We ended up doing a little minor surgery--under anesthesia the vet removed the cartilage at the very tip, debrided the skin so there was clean tissue and put in two tiny sutures and I posted that ear--without taping all the way to the end and used a band aid per above. When the tip healed we removed the sutures and that ear was maybe 1/4 or 3/8 of an inch shorter than the other ear but really wasn't noticeable.
Hopefully you won't have to do that.
dobebug