Why would God be restricted by the matter of His own sacrament? i.e. the physical water in a case where the person was looking after the water/the baptism and they die before they receive it. Or in the case of a martyr. How do you explain how the Holy Innocents are saints on the calendar? Shouldn't they be in the Limbo of Abraham then because water didn't pour over their head? The Church tells us that they are among the saints because they died as witnesses to Christ/directly for Christ.
The attached snapshot is from "My Catholic Faith - A Catechism in Pictures"
I'm not going to be able to debate it with you like a theologian, nor even on your level as you seem very researched on the topic, and have the background in the seminary, but I have an open mind and want to understand. I know there are dozens of threads on this topic here on Cathinfo. I just don't see what holds up the other side of the debate. Outside the church there is no salvation. Not everyone who says Lord Lord shall enter the kingdom of heaven, yes. Only baptism with water gives the indelible character, yes. But is God without mercy like a puritanical God, and limited by physical water?