I'm not sure if there is really a shop in Hokkaido called Shinya. But the lady said that the chef had a restaurant up there and was doing this pop-up at Meidi-ya's Great World outlet through next Wednesday. It's at the end of the strip of food stalls where Nishiyama used to be.
The rice was quite fragrant and the chicken nicely grilled and tender. Healthy and nice.
Hokkaido Dosanko Plaza is a new food hall by Meidi-Ya in Great Word City. There is also Food Plaza which offers ramen, gyoza, bento sets and desserts.