Can PVC be encased horizontally in concrete
PVC pipe embedded in concrete should be fine under most codes I've seen.  You'd need to sleeve something like black, galvanized, or no-hub iron pipe, but PVC and ABS are impervious on any reasonable timeline (~hundreds of years.)

You could have your inspector come through before the pour to check out your plumbing permit if needed.

And the diagram worked great, I think I understood exactly what it was conveying.