Even though he is not your dependent,* he still does NOT qualify for the AOC, because of the earned income rule. He does NOT "meet all the other qualifications". The Earned income rule is an additional rule for full time students under age 24.
If he only has $4000 of income, his standard deduction, alone, would reduce his taxable income to 0. He would not need the education deduction at all.
*Nothing you have described explains why he does not qualify as your dependent.
