Moukoko, who was born in Cameroon, scored against Austria on Monday before following that up with a brace against the same team two days later.
His outstanding performances have led to questions over whether he is actually 12 years old, however, and his father has been forced to rebuff them.
"Straight after the birth, I registered him at the German embassy in Yaounde," Joseph Moukoko told the BBC. "We have a German birth certificate."
Germany's football federation has also staunchly defended Moukoko, who has scored a staggering 13 goals in five matches for Borussia Dortmund's U17s.
"The DFB has already had a number of intensive discussions with Borussia Dortmund at various levels," they said in a statement.
"There is no doubt about the correctness of the age of the player."
