just watched first three and here are my thoughts so far...
i listen to firstborn argument he tricked them but they were undone by lack of bible knowledge on that one.
Genesis 48:13-20 (New International Version)
13 And Joseph took both of them, Ephraim on his right toward Israel's left hand and Manasseh on his left toward Israel's right hand, and brought them close to him. 14 But Israel reached out his right hand and put it on Ephraim's head, though he was the younger, and crossing his arms, he put his left hand on Manasseh's head, even though Manasseh was the firstborn.
15 Then he blessed Joseph and said,
"May the God before whom my fathers
Abraham and Isaac walked,
the God who has been my shepherd
all my life to this day,
16 the Angel who has delivered me from all harm
—may he bless these boys.
May they be called by my name
and the names of my fathers Abraham and Isaac,
and may they increase greatly
upon the earth."
17 When Joseph saw his father placing his right hand on Ephraim's head he was displeased; so he took hold of his father's hand to move it from Ephraim's head to Manasseh's head. 18 Joseph said to him, "No, my father, this one is the firstborn; put your right hand on his head."
19 But his father refused and said, "I know, my son, I know. He too will become a people, and he too will become great. Nevertheless, his younger brother will be greater than he, and his descendants will become a group of nations." 20 He blessed them that day and said,
"In your [a] name will Israel pronounce this blessing:
'May God make you like Ephraim and Manasseh.' "
So he put Ephraim ahead of Manasseh.
ephraim got the firstborn blessing instead of the rightful firstborn menessah which is acknowledge by Jehovah in Jeremiah.
So basically firstborn does mean firstborn but in this case the younger son was given the blessing for firstborn and Jehovah stood by that acknowledgement. the guys uses this eroneously to make a case that firstborn doesn't mean firstborn which is silly.
there is no context to show that Jesus is not the firstborn in a literal sense of Jehovah. he tries to say Jesus created ALL therefore he couldn't be created but the word ALL is not everything the use of ALL is used to apply to a number of things and not the one who deals with the all.
You can see this in another scripture,
1 Corinthians 15:26-28 (New Living Translation)
26 And the last enemy to be destroyed is death. 27 For the Scriptures say, “God has put all things under his authority.” [a] (Of course, when it says “all things are under his authority,” that does not include God himself, who gave Christ his authority.) 28 Then, when all things are under his authority, the Son will put himself under God’s authority, so that God, who gave his Son authority over all things, will be utterly supreme over everything everywhere.