Here are examples of ACIM quotes which specifically speak to God having created many minds. This means, these minds are REAL, are PERMANENT, and are NOT part of the ego dream of separation.
This is part of why "one mind" or "one dreamer" is false. There is not just one dreamer any more than there is just one mind. This is why Jesus says "together we will watch the world disappear".
"God's memory is in our holy minds"
"And peace will be restored forever to the holy minds which God created"
"How holy are our minds!"
"If you allow yourselves to HAVE in your minds only what God put there, you are acknowledging your mind as God created it."
"And peace will be restored forever to the holy minds which God created as His Son"
"Miracles are the way in which minds that serve the spirit unite with Christ for the salvation (or release) of all God's Creations"
"Every mind contains all minds"
"all the minds which God created one with me"
"Heaven Itself is reached by empty hands and open minds"
"You ARE the Kingdom of Heaven, but you have let the belief in darkness enter your minds, and so you need a new light."