I think hte form and such already made it clear it was alien
__________________ Kyuzo: Don't you see? A real sword will kill you. Mr. Earl Brooks: If I were here to kill you, you would already be dead. Mercedes: My mother told me to be wary of Fauns. Mr. Le Chiffre: No, I believe in a reasonable rate of return. James Bond: Now the whole world will know you died while you were scratching my balls!
Another analogy might be that KOTCS Alien Skull reveal situation was like Raiders having the ark blowing it's load and melting the nazis just after the boulder escape then just showing Indy packing and dusting the Ark and shipping it for the rest of the movie..