Nephilim and Giants. Genesis 6

Firstly, I'd like to point out that i know "Sons of God" refers to 'Sethites' and not angels. Thomistic metaphysics states that angels cannot procreate.

What I personally think from research (e.g. Ven. Anne Catherine Emmerich, The Book of Enoch, Flavius Josephus etc) is that Demons possessed either the human male/female, and somehow affecting/manipulating the human act of procreation, gave birth to the giants. A veryyy wise priest of the FSSP who teaches Thomistic Philosophy told me in the Old Testament, evil/satanism and possession was greater than today, that it physically manifested in the human form.

I know they existed pre-flood, my question is this;
How were there Giants after the flood?
(Deuteronomy; I, II & III Kings etc)

Ven. Anne Catherine Emmerich says that not only were Noah, his wife, his 3 sons and there wives aboard, but also Noah's grandchildren (adding to almost 80 people). Is it contra any doctrine/dogma to think there was more than the mentioned 8? Because she then says that HOM, an adopted child of Cham, son of Noah, was "imperfect" in his generations. And also, that Cham/Ham, consumed a poison made by antedeluvian sorcerors which made his descendants corrupt... or something along those lines.

The giants couldn't have survived outside the arc (on mountains etc), because "All flesh was destroyed". Therefore, one (if not two) of these four propositions must be true;

1) Either Ven. Anne Catherine Emmerich was right, and there were more people on the arc, i.e. Hom (the adopted son of Cham/Ham)

2) That Cham/Ham had consumed a curse by an antedeluvian sorceror which affected his seed.

3) That possibly, Noah's wife was not "perfect in her generations".

4) Flavius Josephus in "Antiquities of the Jews" says that, the Sethites built two pillars to preserve ancient knowledge in case of either a flood or firestorm. These, he called, the Pillars of Siridan, which are the two Pyramids at Giza. Could this be the answer? That the surviving humans post-flood rediscovered the ancient occult secrets. This would explain why Egypt was the culmination of all things evil in antiquity, and their knowledge of Astronomy etc which is unexplainable.
(THIS MAKES MORE SENSE TO ME OUT OF ALL OTHER PROPOSITIONS)

Please feel free to deconstruct my post and correct me!
GOD BLESS!

Proof? I'm 6'4".

Who can say exactly how tall but back in the day...........


How tall was Goliath?
Most English translations of the Bible (e.g. NASB, NIV, KJV, NRSV), following the Masoretic Text of the Old Testament,1 say that Goliath was six cubits and a span tall. The ESV, for example, says the following:
And there came out from the camp of the Philistines a champion named Goliath of Gath, whose height was six cubits and a span. [1Sam. 17:4]
Converted into more modern measurements, this is 3.2 metres (9 feet, 6 inches), if measured by the 18 inch cubit, or 3.5 metres (just over 11 feet), if the 21 inch cubit is used.