So a recent quack tried to predict the end of the world and failed.
I don't question his dedication to his chosen path. I do question his mathematical skills. And by that I mean the ones specific to biblical mathematics. For those who do not know this obscure form of math, phrases and words have values and adding the values together supposedly give one the "end of days."
The real problem in this situation is that this person was using mathematics that were meant for the Talmud. Jewish scholars have developed a very intricate set of mathematical functions. Some call this a section of the Qaballa. But the math involved supposedly does involve things like the end of times.
But those mathematical functions do no transfer over to other religious books. Just like subtracting 1 from 20 does not equal 20 times 1. It is like using Japanese kanji to translate Chinese. Words may be similar, but sentences will be obscured.
Want to figure out when the end of the Earth will happen? Figure out when the Sun goes Supernova. That is the most correct answer. And show your math.