I haven’t read anything about Bahai and therefore, I am not the suitable person to pinpoint their false allegations.
I say that their allegations are false with confidence as I believe in my religion and I believe that this is the religion that Allah had completed and accepted to be our religion as mentioned in chapter 5 verse 3.
The authenticity of the Quran and the Sunnah is not claimed only by scientific facts. It is claimed through the social, legal and moral system it provides.
Bahai predictions are like any predictions that can have some truth to it and a lot of falsehood. I am sure and certain that if you go through all of his predictions that you will find this and also sense it while in Islam, this can’t be found as this religion is from Allah who revelead the Quran and the Sunnah. Therefore, to claim that after the religion was perfected and after Allah has told us that Mohammed salla Allahu alaihi wa sallam is the seal of the Prophet hood and that there is no Prophet after him, to claim that this is not true and that there is surely another Prophet and another religion, this means that one of the two is not correct; either Quran is not the word of Allah or that the person claiming to be a Prophet is a liar.