When racing for either RedBull or VCARB at Suzuka in the new DLC, Marc still says: "This is our engine supplier's home Grand Prix".
This seems to be leftover dialogue from when these teams were associated with Honda. In the new DLC, RedBull/VCARB are linked with Ford/RedBull Ford Powertrains, so Suzuka should no longer be treated as their engine supplier's home Grand Prix. Instead it should be America.