This thesis is clearly refuted by the findings of much older (-800 000) remains of humans outside Africa. See for instance <a href="https://en.m.wikipedia.org/wiki/Peking_Man" rel="nofollow">https://en.m.wikipedia.org/wiki/Peking_Man</a> .
IMHO the most credible origin of man is that there are multi-origins : humans were separated 1M years ago and evolved independently.