Brave rescue kitten needs surgery

This brave 12 week old kitten was rescued by my co-worker a few weeks ago on the old airstrip in Tuba. His tail had been severed, and he was initially very sick, but after antibiotics and TLC, he improved into a curious and sweet kitten. Nathan and I were so happy to adopt him and bring him home to join the family! We named him Brule, which, in addition to being a sweet dessert, also means a forest which has been burned and is ready for regrowth. We have been amazed at the gentleness and love displayed by this animal who spent much of his early life in pain. A few days ago the scab covering his wound fell off and revealed a large piece of bone protruding through the skin. The vet is worried that without surgery, the bone will become necrotic and Brule could die of a bone infection. In addition, the surgery must be done by a specialist since the tail was severed so close to the body. This is an unexpectedly large expense but necessary to give Brule the best chance of a happy and healthy life. We would greatly appreciate any help you could give. Thank you!