I think you have misunderstood the time distortion possibilities. Jordan makes allowance for 10 hours to 1 hour or the other way around. What you are suggesting is a distortion of 7 or 8 years which is highly unlikely. Unless Jordan were to say that the soul of a hero isn't per se "born", instead, injected at the moment the pattern sees fit...but I believe Birgitte mentions birth so I don't see that as a possibility.