Was Daniel's revelation of the forgotten dream just a coincidence or human happenstance?
No. Daniel's receiving the forgotten dream was not coincidence or human happenstance. The secret was revealed to him in a night vision because the almighty sovereign God was at work. God Himself revealed to Daniel the dream that Nebuchadnezzar had forgotten, showing divine intervention rather than human ability.
Les explains that Daniel, still a young man without gray hairs or age-based respect, spoke up with counsel and wisdom to Ariok, the captain of the king's guard. Daniel asked the king for time and said he would show the interpretation. Then the secret was revealed to Daniel in a night vision. Les emphasizes that this was the almighty sovereign God at work, not human happenstance. God revealed to Daniel the dream that Nebuchadnezzar had forgotten. When Daniel stood before the king, whose name had been changed to Belteshazzar, he testified that the wise men, astrologers, magicians, and soothsayers could not show the king the secret, but there is a God Nebuchadnezzar knew nothing of. Les also reminds his classes that since the tower of Babel, the human race has been saturated with idolatry.