Okay, this rewording makes more sense.
Now your P2, once reworded says "Necessary Metaphysical Naturalism is possibly true" vs "A necessary being possibly exists"
This raises some questions for me:
1) What does necessary metaphysical naturalism entail? That nMN is true in all possible worlds? This is answered for God in the context of the MOA.
2) How do we establish the property of necessity applies to MN? This is argued for in the MOA by saying a MGB cannot be contingent.
Now your P2, once reworded says "Necessary Metaphysical Naturalism is possibly true" vs "A necessary being possibly exists"
This raises some questions for me:
1) What does necessary metaphysical naturalism entail? That nMN is true in all possible worlds? This is answered for God in the context of the MOA.
2) How do we establish the property of necessity applies to MN? This is argued for in the MOA by saying a MGB cannot be contingent.