Tournament is scheduled over 34 days.
You could put in 10 games at one stadium, if they did 5 group-stage matches, one round of 32, two round of 16, on quarter-final, and one semi, and still keep 3-4 days between matches.
But it won't happen. More likely that they'd use two venues in Toronto, or reduce the number of games in Canada to 7-8.
In the 2026 bid book, USA is putting 60 games in 10 only stadiums. Most stadiums got 6 games. One gets 7 (with no semis nor final).
And in Qatar, Lusail Stadium IS getting 10 games, despite the tournament only being 28 days, compared to the 34 days for 2026. And there's three 4-day gaps in there!
If the Jays get a new stadium near East Harbour station (the quayside alternate in that article) , I'd be surprised if it's done by 2026 - especially as the subway won't open until 2030 or so.
But if they do, it could be ideal, as you could put grass in the Skydome earlier and for longer ... before imploding the entire structure.