CathInfo.com

Yes, Fr. Cekada clearly proves BOD is at least theologically certain Catholic Doctrine, and thus an objective mortal sin to publicly deny.

Here is Pope Bl. Pius IX in Tuas Libenter: "2879 Dz 1683 While, in truth, We laud these men with due praise because they professed the truth which necessarily arises from their obligation to the Catholic faith, We wish to persuade Ourselves that they did not wish to confine the obligation, by which Catholic teachers and writers are absolutely bound, only to those decrees which are set forth by the infallible judgment of the Church as dogmas of faith to be believed by all [see n. 1722]. And We persuade Ourselves, also, that they did not wish to declare that that perfect adhesion to revealed truths, which they recognized as absolutely necessary to attain true progress in the sciences and to refute errors, could be obtained if faith and obedience were given only to the dogmas expressly defined by the Church. For, even if it were a matter concerning that subjection which is to be manifested by an act of divine faith, nevertheless, it would not have to be limited to those matters which have been defined by express decrees of the ecuмenical Councils, or of the Roman Pontiffs and of this See, but would have to be extended also to those matters which are handed down as divinely revealed by the ordinary teaching power of the whole Church spread throughout the world, and therefore, by universal and common consent are held by Catholic theologians to belong to faith." From: http://www.clerus.org/bibliaclerusonline/en/dxm.htm

I'm still waiting for anyone to show me (1) A Theology Manual, post Trent, that says BOD is disputed. (2) Any Church Doctor in the whole last millenium that denies BOD, particularly after Pope Innocent III. St. Bernard, St. Bonaventure and St. Catherine all teach it.

Syllogism:

Major: Catholic Theologians post Trent unanimously say that the Council of Trent taught Baptism of Desire.
Minor: What Theologians unanimously teach as having been taught by the Church is guaranteed by the OUM.
Conclusion: Therefore, the Ordinary and Universal Magisterium of the Church infallibly guarantees BOD is true.

With regard to the alleged counter-example proposed, how many ever said "The Church teaches unbaptized infants suffer fire in hell"? Neither did the Magisterium or any Pope endorse this rigorist opinion. Some Fathers, especially St. Augustine, expressed their personal opinion on the matter. But the Church ruled otherwise and closed the question in teaching, just as St. Thomas had said, that little infants who lack Baptism suffer only the supernatural privation of the beatific vision, and enjoy perfect natural happiness in limbo. Limbo actually is a perfect example of Church doctrine being closed by the Magisterium, in opposition to the erroneous views of 1 or 2 Fathers.

Just like the Church taught Limbo, She also clearly taught BOD. Catechisms have taught Limbo to the Faithful and the same Catechisms have also taught BOD. It is the ruling of the Church, in closing the question, that obliges us to assent to the Catholic Doctrine of BOD.

Major: Catechisms approved by the Church for centuries and used by Bishops throughout the world have taught BOD as divinely revealed Church Teaching.
Minor: But the Ordinary and Universal Magisterium of the Church cannot teach error for centuries in what it proposes as divinely revealed Church Teaching.
Conclusion: Therefore, the Ordinary and Universal Magisterium of the Church once more shows us that BOD is divinely revealed Church Teaching.

There is a final consideration from the manner in which the Popes have authorized St. Alphonsus' writings, the Theologia Moralis where he defines and teaches BOD in particular, as safe for any Catholic to follow - even while not knowing the reason whatsoever behind it.

From: https://www.goodcatholicbooks.org/alphonsus/alphonsus-facts.html

Major: Popes have said St. Alphonsus can be safely followed in what the Doctor taught in Theologia Moralis.
Minor: St. Alphonsus teaches that Souls are saved by BOD is de fide because of Trent in Theologia Moralis.
Conclusion: Therefore, all Catholics - even without knowing reasons - can safely teach BOD is de fide dogma.

I personally usually say "BOD is Catholic Doctrine" rather than "BOD is Catholic Dogma" but the latter can be safely said, per the Popes.

There is no chance that the Church will ever condemn BOD. BOD is irreformable Catholic Doctrine at minimum. St. Alphonsus also teaches explicit faith in the same Theologia Moralis, and all Catholics can also safely follow him in that. The Church has spoken.

Yes, Fr. Cekada clearly proves BOD is at least theologically certain Catholic Doctrine, and thus an objective mortal sin to publicly deny.

Tell that to the SIXTEEN (by my count) out of 25 theologians he surveyed who did NOT hold that it was "at least theologically certain."  They evidently don't agree with Fr. Cekada's "proofs".