50's poured foundation without exterior form?
It seems unlikely. Concrete is expensive, and has always been.
Formwork is reusable, and you don't waste twice as much concrete pouring the foundation if you use formwork. In most areas, the dirt will not stay put well enough to pour a wall directly against dirt.
It's possible, but does not seem terribly likely. Then again, most egress windows are not all that low in the wall, so if it was &quot;the first pour&quot; (footing, which is below floor level) it should have no interaction with your window - at which point I'd be thinking &quot;hmm, is this contractor setting me up for an upcharge?&quot;