To be honest, I'm not sure. The last I heard was that there was a lawsuit filed against the band. And I know the bus driver was charged with something. I'm pretty sure the band did donate some money for environmental causes. Then again, they do that constantly as it is, but I think they donated something to Chicago, specifically.
Fact is, the band had nothing to do with it. The bus driver's contract with the band had ended when this thing happened. The driver was on his was to St Louis (I think) from Chicago after that leg of the tour had ended. No band member was on the bus when it happened.
I'm pretty sure that that bus driver will no longer be hired by the band (if he even has his job anymore).