If Mr. Al-Kadhi had read these verses more carefully, he would have seen that they do not refer to science or past history. They refer to prophecy. Muhammad did not correctly predict any future occurences ... not even his own death (Qur'an 3:144) ... unlike Jesus who prophesied his death and resurrection to his apostles.
As shown in section 6.12, Muhammad was not truthful because he did not glorify Jesus. Muhammad rejected that Jesus had come in the flesh.
Besides, a scientist can be 100% accurate about his theories. This wouldn't make him truthful in spiritual matters.
Was truthfulness always his highest priority? You might want to ponder Bukhari, Volume 8, Book 73, Number 59o.
`A'isha was able to see the inconsistency.
The Rebuttal to "What Did Jesus Really Say?"
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