That relies on the assuption that they’d use the long route across the central Pacific. The further south you go, the shorter the trip gets. And if you go south off the coast of Tasmania, you go straight into a strong. stable current that goes straight to South America without hitting New Zealand or much chance of any islands on the way.
Its still an excpetionally long trip, and even in the faster areas of the current you’d take a long time (200 + days) in a very dangerous ocean.
I’d call such a crossing very unlikly, but with a number of people swept off to sea over tens of thousands of years, I couldn’t call it impossible that a single couple/group survived it.
If such a group survived up to the time where contact with the Spanish occurred, that doe smake me wonder about the Olmec stone heads, which seems to have no connection with Africa.
This Wikipedia page says: “The general physical characteristics of the heads are of a type that is still common among people in the Olmec region in modern times.”