Fried motherboard or?

I believe my laptop was shorted, someone tried to rewire my charger cord after the dog chewed and split it and now my laptop will not turn on. The laptop is not taking in power, I bought a new charger, which is compatible but the laptop still wont turn on. Could it be a fried motherboard? How much would it cost to get that replaced (including labor) roughly? Could it be something else, maybe something not quite as bad? Thanks for the help.