Good question.
However, it is somewhat irrelevant because even if God told Eve Himself, Adam was still told first and knew what God had told HIM.
And he STILL watched the exchange between Eve and Satan and allowed her to eat.
Adam had been given dominion over all the earth. The responsibility was his.
I remember some guys in college saying, “If it wasn’t for women, we’d still be in the Garden of Eden eating strawberries.” ;o)