I post it here because it’s clearly an overlook. Other Nissan’s Super Silhouette cars (Bluebird and Skyline) are eligible for this event, as well as the 1985 Buick Somerset Regal Trans-Am (also a DLC car), so there is no reason to exclude Silvia.
I wanted to use that car in this event so badly… It could be the first occasion to use any paid vehicle in career mode (excluding those 3 recycled road cars from Car Pass)…
I hope it can be hotfixed before the Retro Racers Tour is over.