Anyway, as to:
Promoting the supposition that Matthew wrote the gospel in Hebrew but there is no documented proof . .
As to Matt. 16, the point is simply that Aramaic was the common language of the day. (See, e.g., Mark 15:34-36) So when Jesus is speaking to the Apostles that day at Ceaserea Philippi, he's speaking in Aramaic. And clear evidence that Simon was called by the Aramaic "Kepha" is found in John 1:42;
42 And he brought him to Jesus.
Jesus looked at him and said, “You are Simon son of John. You will be called Cephas” (which, when translated, is Peter[a])(NIV).
The footnote to that edition states: "a. John 1:42 Cephas (Aramaic) and Peter (Greek) both mean rock."
"Cephas" is a transliteration into Greek of the Aramaic "Kepha" (rock).
So the point that in rendering the dialogue into Greek, Matthew had to contend with the noun gender in Greek (thus choosing "petros" (masculine)) doesn't depend on proof of some original Aramaic manuscript to Matthew's Gospel, just on recognition that the words spoken to Peter were originally spoken in Aramaic.
Do you really want us to take your comments seriously? The common language beginning already in 300BC was Koine Greek, not Aramaic. What language Jesus was speaking is irrelevant in that the Holy Spirit inspired the New Testament to be written in Greek. Do you honestly think that the Holy Spirit didn't know what words to use to convey His meaning?