He is the offended party. He has reconciled all TO HIMSELF. not Himself to us. We must believe He's done that per the Gospel of grace (not tulip) to be saved. There's no disconnect there.
The doctrine of reconciliation is a road block for the Calvinist. They cannot understand how God has reconciled the whole world unto himself by Jesus Christ, so they reject it.
When they reject the doctrine of reconciliation they reject the Gospel and place themselves outside of the faith.