Wow. Of course it was God's will. But why, was the question.
Unless your argument is that it was Gods will to preserve the mss in Aramaic and His will was thwarted by someone or something, there is no possible doubt on the point.
I've never made that argument.
If you concede that A, God directly and actively chose Greek for His NT revelation, and B, the God-breathed words of Scripture are inerrant, then the entire Aramaic discussion is an u justifiable waste of time. We have the divinely inspired words of Scripture in the exact form that God willed for us to have them in.
Re the why: Greek is more precise than Aramaic. It is the perfect language in which to communicate with maximum clarity and minimal ambiguity.