First off, sorry about what happened.
Second, do not try to repair it yourself. It sounds like your bird is under warranty. Call DJI and get an RMA number. I had pretty much the same thing happened to my Phantom and it was about a month from purchase. I called DJI, got an RMA number and FedEx it back to them. After about 2 months, I finally got it back, pretty much as good as new.
Yes, 8 weeks is a long time for repairs but I think they're getting better. They were constraint by parts at the release but I think it's improving. Lately you can't get through on the phone but if you email and ask them to initiate the RMA process by email because you can't get through, they'll send you an RMA number by email. If you're lucky, you'll get an escalated RMA which means a free FedEx label saving you around $20.
I know DJI has a bad rep for service and some of that is deserved. It's nigh impossible to get a hold of them on the phone but they're responsive by email. The repair times are long but then again, I'm not sure how long to expect or what is reasonable. In my case they took care of me with pretty much the same damage as you describe without any cost to me.
I have another drone in now for other warranty work but before you attempt this major repair on your own, try DJI. A gimbal, broken ribbon cable, possible camera damage and motor damage as well as a cracked case is no small thing. Good luck!