Indeed, the Qur’an refers to the impotence of these other gods:
He [God] to Whom belongs the dominion of the heavens and the earth and Who has begotten no son and for Whom there is no partner in the dominion. He has created everything and has measured it exactly according to its due measurements.
Yet they have taken besides Him other gods who created nothing but are themselves created and posses neither hurt nor benefit for themselves and possess no power [of causing] death nor [of giving] life nor of raising the dead.[3]
It could be argued that both gods might cooperate instead. However this scenario does not reveal the independent Will that is the exclusive characteristic of God as the Uncaused Cause. Therefore, the scenario of cooperating gods cannot distinguish divinity between one or many gods. There is of course no reason gods would cooperate in any case.
Indeed, the Qur’an refers to rivalry that would occur if there were many gods:
No son did Allah (swt) [God] beget nor is there any god along with Him. [If there had been many gods] then each god would have taken away what he had created and some would have tried to overcome others! Glorified is Allah (swt) above all that they attribute to Him![4]
So this rivalry would involve the destruction of the universe as each god used their creation to fight each other.
Had there been therein [in the heavens and the earth] gods besides Allah [God] then verily both would have been ruined. Glorified is Allah (swt) the Lord of the Throne, above all that they associate with Him![5]