No. The genomes tell a pretty clear story. Should your hypothesis be correct, you would find haplogroups in the 45kya group descended from the 60kya austronesia

No. The genomes tell a pretty clear story. Should your hypothesis be correct, you would find haplogroups in the 45kya group descended from the 60kya austronesian group - but you do not. Rather, you find a most recent common ancestor before the 60kya group left Africa. As to why Africa - this is where ancestral hominids and the earliest known sapiens specimens have been found. While we have found cousins elsewhere, the evidence all points towards sapiens having emerged in Africa and spread elsewhere in successive waves. When the hypothesis first appeared it was somewhat shocking to science, as the leading theory was some sort of parallel emergence of the races - but this was not grounded in the evidence being found in Africa at the time, and genetic evidence has since cemented this not as hypothesis, but well-established theory.