I'd have wanted to see the inside of the diff after that. If there was excessive wear I'd have gotten a new axle. Every time it made that noise it was scrapping metal off your gears accelerating the aging process.
Story time: In the 90's I bought a used Dodge Raider. I had it 2 weeks and the 5-speed manual transmission literally fell apart while I was driving. The dealer gave me some bullshit about how they will fix it but I have to pay half. I said fix it or keep it. They fixed it. As part of the issue it damaged the clutch plate, flywheel and main seal. In the process of doing that they screwed up the oil pump. I didn't even get home before the engine ceased. The oil pressure gauge was not hooked up properly and showed pressure but there was no oil flowing anywhere. They said this time that I had to pay 25%. Again, fix it or keep it. I picked the vehicle up after it's second rebuild and never darkened their door again nor paid a cent. I paid that vehicle off before the end date and never looked back. After their work it ran for another 8 years until the roof rusted off of it.
Moral: Remember who the customer is and don't let them forget it. You don't have to be a jerk about it but you more definitely need to be assertive.
People get the service they deserve. If a service place has incompetent people, argumentative service reps, or just plain ignorant people about the product they are servicing, you can go elsewhere. Even if it is a further drive. There are always options. Consumers vote with their dollars. Too many people just sit and take it or just don't understand so blindly trust their service people without any question. It doesn't take much research to find out how your vehicle works and unless you are very anti-social you are bound to know someone who knows someone who actually has a clue that can help you if you don't.
(steps down off soapbox)