Yes I think you should just cough up the fines. If it's that big of a deal then like PPs have said.. tell them the truth. Don't lie to them. By lying you are potentially getting someone in lots of trouble if they haven't crossed off both your names.. they aren't going to believe that they didn't cross of both you're names either and you'll just look like a tool. Don't try and get someone else in trouble for your mistake!!