So I had my cake all iced and decorated but when it was time to transport, so many things went wrong!

I'd made and stacked a buttercream cake that was two colors, one tier hot pink the other two brown/leopard. Everything was fine until it came time to take the cake.. my ac in the car went out (just before I was supposed to take the cake, go figure!!), it was cool outside but even with the windows open it was rather hot. Driving through the tunnels of Boston in 5 o'clock traffic, it became stifling in the car. All the stop and go, the cake actually slid across the board it was sitting on, mind you it was dowelled, and it hit the back seat and a chunk of the leopard is gone and the hot pink middle tier is dented. *sigh*

So my question is, how do I fix the hot pink tier without taking the cake apart? Smoothing with a bench scraper and extra icing while its cold? I've seen it done but I don't think I'd be able to pull it off myself. Help!!