Spoke to the vet several times yesterday. At this stage, fingers crossed, the only injury Rennie has is a broken tail. The vet was going to do a full body x-ray to make sure he hasn't missed anything. Unfortunately due to the severity of it, it looks like the tail will have to be amputated. And she (Rennie is a girl) has such a beautiful, fluffy tail.
Thanks guys for all your best wishes.