Still though, if all these doctors and saints are hinting at an adult limbo, there should surely be quotes from at least some of them explicitly saying it, right?
Why do you think I call it Ladislausian soteriology?
I'm building the case from the Fathers and from Sacred Scripture and applying various theological arguments. What do you think that these doctors, saints, and theologians do?
Father Feeney came the closest, but he did not take the next steps.
I do not deny the existence of a BoB or even perhaps a BoD, but I apply the teaching of St. Ambrose and St. Gregory nαzιanzen, and Sacred Scripture, and an understand of what the character of Baptism does and what is role or function is in soteriology.
Even BoD proponents agree that BoD/BoB only supply the one effect of the Sacrament, namely, the remission of sins. It does not supply the character of Baptism nor does it render the subject a member of the Church.
St. Ambrose refers to this as a "washing" without "crowning" ... even for martyred catechumens.
I hold that the crowning, the seal, what St. Gregory nαzιanzen calls "the glory" are essential to the Beatific Vision, which cannot be had without them.
Consequently, a martyred catechumen would have all his sins washed but still not enter the Beatific Vision.
ergo, an adult in Limbo
Now, the reason that unbaptized infants go to Limbo is because they have no actual sin. But a martyred catechumen would have his actual sin washed away.
Not only that, but I hold that a martyred catechumen would have even a greater degree of natural happiness than an infant who died without Baptism.