Even the koranic god Allah does not claim absolute oneness for himself. If so where do we find this in the Koran? If God says he is one something, Lord or God, then that is a different statement. It is a claim of absolute oneness in relation to another thing of the same kind, even though that thing as created tends to nothing, a sum to infinity of zero, when compared to God.
It could be argued that the koranic Allah could not be one because if he was he would not be free to be good or evil towards anyone he wanted. If he is free to guide or to lead astray then he must be at least two in his will in order to choose both possible choices for each human being that he has created. So he is not one in his will. His will must have the freedom to guide or to lead astray from the right path any particular person any number of times he chooses. He must also have the freedom to cast any Muslim in to hell even after he has been in paradise for a million years because the slavemaster must always be free to act in any way he wishes towards his slaves, and Allah is nothing if not a slavemaster in the sky.
Absolute oneness has it’s problems, even for Allah. Therefore he cannot be one.