engine repair

I took my wifes vehicle in because of engine trouble. He took it apart and tells me its contaminated gas. Well since he pulled all of the gas out of the vehicle insurance wont cover it. He showed me samples of gas. I took a sample of the same gas and let it sit out to replicate what he showed me and it nothing happened. He then said he found the problem fixed everything. He replaced the fuel rail, injectors, the valve that was causing the misfire, and a broken timing chain guide. He went to take it for a test drive and the motor blew. so I was $4k into this and he couldn't even give me a running vehicle in return. on top of that it had a small vibration coming from the center of the vehicle and proceeded to tell me it was mud in the wheel wells. I knew that wasn't the issue. Come to find out it was coming from the transfer case. If you take your vehicle to this guy your wasting your time and money. He doesn't know what hes doing.