At around 4 minutes into the September 2015 video Splane said "For
the man and the baby to be part of Josephs generation they would have
had to have lived at least some time during Joseph's lifespan."
An easy way to debunk the Josepeh idea is to read Genesis 50: 22-23:
22 And Joseph continued to dwell in Egypt, he and the household of his father, and Joseph lived for 110 years. 23 Joseph saw the third generation of Eʹphra·im’s sons,+ also the sons of Maʹchir,+ Ma·nasʹseh’s son. They were born upon Joseph’s knees.
Ephraim was Joseph's son by his wife Asenath.
So Joseph lived for how long? 110 years.
And he saw how many generations in that time? He saw the third generation of Emphriam's sons but you could therefore say he saw 4 (including Emphraim).
Deary me David, Don't ya just hate it when the Bible doesn't support your crap?