Fix my pups broken jaw

poor guy is 12 weeks old, we brought him into our family on the 8th.  He was biting at our big older dog and she nipped him(she’s 100lbs).  She was fed up and I was busy helping my boys out with breakfast.  We never ask for help but at this this point we need it, he’s a very energetic Dachshund.  We love this little guy already, anything is appreciated and would bring happiness to us to keep this guy in our family. On Monday the 11th we go In for a specialist to check him out. The vet told us today it’ll be around 5-6 thousand. Please help.