Considering what she wants to achieve and what she is already doing, opening a second shop is not a very bright idea, especially on the long term: the only reason she has so many clients is due to the novelty of her recipes.
Once the academy will start churning out 20-40 new chef severy year, all trained by her on Japanese cuisine, the hype will quickly die, as well as the influx of clients. Just keeping her current establishment afloat will require some serious thinking, and possibly a rebrand.
Since her objective is spreading the cooking knowledge, she should focus on the academy, keeping the café business at a small scale, catering to the wealthy and influential: it will exist basically as a showcase of what you will get from the culinary course, and a place where her new recipes are premiered, before getting sold to the chefs she trained.