After 6 weeks of control chains problem

Hello sorry if I’m in the wrong area then please move to the right one. Now to my problem. I bought a Seat Alhambra at the end of April. Now after six weeks suddenly the lamp of catalyst goes on I immediately slowly drove to the next workshop at us around the corner (seat dealer). They have read out the car and determined that the control chain has skipped. Approx. cost without offer 1500 €. Have now phoned with the dealer where I bought the car have between me and the seller at least 300 km. They would repair the car with themselves, I have the legal warranty for used cars at the dealer. Now the car should go there. I should deliver it, but the car is not so ready to drive. Now the questions: Does the car have to be repaired there? If so, who has to take over the transport or pay. I then have the right to a rental car because it has been with us already 3-5 days before I have the wagon But if he has to go away now, it will take 2-3 days in addition. Maybe someone has some ideas or experience with this and can help me further and or say to if I can apply for it. Thanks already in advance MFG Djschlod