Please ignore my lack of knowledge. I got my son purchased Top Gear Pack which shows installed in the game but when he tries to add the cars mentioned in the pack from , the game still mentions you need to purchase it through credits or tokesn. We were under the impression that once you purchase the pack, all cars in the pack are free to add from the cars section.
They are only free in game for the profile that actually bought the pack…other profiles will have access but have to use in game credits to buy them
If it was bought with his account they should be free in game for him and will be found in the “free cars” tab in the find a car section