It depends what you call "brown rot death". There are several diseases classified by hobbyists and most professionnal as "bacterial" that are definitely not !
I will scan some reports from a PCR lab with pictures of the sicknesses, when I have time.
A soft watery area with brown rot, very fast, can be related to phytophthora, one strain or erwinia carotovora, one yeast, glomerella sudden attack, pseudomonas, and fusarium. They are totally unrelated, but the symptoms will look exactly the same.
The orange gooey roots of paphs can be due to erwinia, fusarium, phytophthora, bremia, and xanthomonas with secondary infection.
For the dry slow rot, it can be again phytophthora, different strain, or your choice of erwinia, xanthomonas, colletotrichum, pythium... and much more.
My experience is that some of those sicknesses are actually very slowly invading the plant, and suddently they will resume and attack.
As an example, most of the plants that have got erwinia never recover on the long term, after some months or years, the erwinia will restart, treated again, and restart some years later. Keep records, and you will find out that it's true, even if the plants looks beautiful for a while after the "cure"...
Plant diseases are not very well understood by many people, but people have to realize that many are systemic, and the "symptoms" are only a small part of the affected area. Second, if you keep the plants dry, the phytophthora, pseudomonas and fusarium on the leaves will make only a few pitting here and there, to resume massively when the weather is better for those sicknesses.
Many chemicals are bacteriostatic and fungistatic, not bactericides and fungicides as well, so it delays the death of the plant, but does not prevent it completely. Sometimes it can delay that death for many months or years A batch of paph gardineri in the Netherlands has systemic bacteria, kept under control with antibiotics, but when moved to others places, the plants die after a couple of months...