Mine didn't work when I bought my car a couple months ago and I fixed it rather easily. May be worth a shot for you to try this as well.
If you go as far as pulling the steering column covers and getting the clear plastic cover off of the cluster, you can take a small pick, or VERY small screwdriver and slowly move the numbers over to the next digit. Then try to press the reset button. if it resets, you should be golden. I then sprayed some silicone lubricant in there. Just a tad, but it should keep from having things hang up.
I used the liquid wrench spray and when I put it all back together, it has worked flawlessly for the last 200 miles or so. Be forewarned, it isn't the easiest task getting everything apart to get in there. It is actually kind of a pain in the ass. I think it took me roughly 2 hours to get to it, get it fixed and put back together and I am VERY mechanically inclined. The way I looked at it was it wasn't working when I got it, so worst I could be was in the same situation I was when I started.
Sure beats buying an $800 cluster and after reading that others had had a similar problem I figured I'd take a whack at it and I am glad I did!