Cleanout location in basement bathroom

[Brian80]

Hi, I'm planning to renovate a bathroom in the basement. I found this video which explains the exact DWV layout I need, but the only problem is that my bathroom is on a concrete slab so the cleanout location in the diagram won't work. My cleanout obviously needs to be above the slab, but I'm not sure where it should go. Can I extend the 3" pipe backwards (against the flow of water) into the nearest stud bay and put the cleanout inside a wall behind an access panel?

In case plumbing codes differ on this, I'm in Canada (BC).