I would disagree. The picture here shows what is called the Great Hall East Wing. The Bay GO Concourse (upper level) is a totally different area, and actually at a different elevation to the East Wing. The area under the skylight and opening in the floor (picture foreground) is the Front Street Promenade, which is connected at grade (more or less) to the TTC, Bay Retail, which is below the GO concourse level and similar elevation to the Food court under the York GO Concourse.
Elevations:
1. Great Hall/East & West Wings/Street level
2. Moats/Promenades & GO Concourses - Scotiabank Arena
3. Food Court/Retail concourses