Never let things slide if you feel your car has a problem. Pursue a solution until you are satisfied you have the answer. It’s not a good idea to miss services, particularly on cars with turbochargers. Keeping a fresh supply of oil is the key to trouble-free motoring with turbos. There’s every chance the turbo was faulty when you first noticed it, and having missed a service you probably contributed to the failure. There’s probably not a lot you can do, except to pay for the repairs.
