Eb was hurt pretty badly. Major leg break like that, even wizard healing is going to take a while before he's fit to leave Edinburgh under his own power. He might not even appear in Twelve Months, unless he's got a bunch of Wardens chauffering him and pushing him in a wheelchair.
My 90 year old grandmother got out of her wheelchair six weeks after she broke her leg. Of course, it was a clean break with no complications. I could see Eb making an appearance late in the book. That would give him most of a year to heal. Plus, it would give Ebenezer a pretty good reason to be using Mother Winter's walking stick. Sort of like using a really big shotgun as a walking stick, but that would be the point, wouldn't it? Just to show everyone what's on his mind.
What I could see happening is Ebenezer arriving and after much tension admitting to Harry that he tried to take out Lara from a distance, but she was protected, just like her father used to be.