Hi Vic,
One more thought. Your copy/paste tells me, "God chose to bring his Son into the world through the cooperation of Mary. Without that cooperation there would have been no Incarnation and therefore no Redemption."
God also chose that Jesus would be born in a stable, wrapped in swaddling cloth, and lay in a manger.
So, using your logic -- the stable, the swaddling cloth, and the manger -- are also Co-Redeemers; for God chose them as part of His actions of bringing Jesus Christ to be our Redeemer.
Interesting!
God bless, have a wonderful, blessed day,
Bill