Sister borrowed car, got ticket, lied to me about paying it and now it went to collections

Title pretty much sums it up. Sister borrowed my car and missed a few toll booths on the highway. Got the tickets in the mail. Few months later got another warning saying i need to pay or it will go to collections. She then said she paid it. Got a letter this AM from collections saying i've failed to pay the ticket. She feels terrible and that she forgot to pay it. Do i have any options here or is this stuck as a hit on my credit? If she is willing to accept liability for the debt (she feels terrible and is)- is there any way to make that happen. This is fucked.