turbo out on 2002 V40

I was on a road trip this past weekend and my oil pressure light came on. I pulled over and checked my oil and added a qt (which turned out to be a qt too much). The light remained on but I was in the middle of nowhere so I continued on to my destination. As I started to accelerate on the on ramp the transmission skipped a few times and the car wouldn't accelerate for the duration of my trip. It took me sometime to find someone to look at my car as I was in the middle of no foreign car land, but when I did the mechanic said nothing was showing up on diagnostics and after a drive it appeared my turbo was out. He thought I would be able to make it home (I did) without causing any damage (???).

I am hesitant to just appear at the dealer as I have yet to walk away from there without handing over $500 plus. I am wondering if this has happened to anyone? How much does it cost to repair (I live in Chicago)? Any good independent Volvo mechanics out there? If my turbo is out will I cause additional damage by driving it? Anyone want to buy my Volvo? It has 49k miles and brand new tires!

Thank you!