From a Muslim’s perspective it is not possible to corrupt the Qur’an for several reasons.
After 1400 years, the Quran still exists in the original Arabic language.
The Qur’an is memorized by heart by many Muslims world wide. Muslims would be able to reproduce it from memory. I know of one teacher at Zaytuna institute in California who wrote out the Quran completely from beginning to end, completely from his memory.
God promised to protect it.
We have, without doubt, sent down the Message; and We will assuredly guard it (from corruption) (Quran 15:9)
All of that aside, But what if…
One of the main doctrines in Islam is God’s Justice. It can be classified as Justice through creation and Justice through legislation. By creation I mean all of what He created, the universe and everything in it. By legislation I mean his laws, orders and commandments. Complete Justice belongs to God.
When we look in nature there is nothing out of place, and everything has its measure, course and order set by God. From the orbit of the stars and planets in our solar system to the sustaining of Life on this earth; the natural order in nature is Perfect. This natural order leads us to conclude that divine justice alone balances the scales.
This concept extends to His legislation as well, He sends exemplary messengers to teach us His message, his orders, commands, oughts and ought-nots. If His message becomes corrupted then his Justice demands He sends another messenger with the same message or at least protect the message from being corrupted. Otherwise we are left lost, in a catch-22 situation where we are required to follow God’s commands without knowing what it is.
I hope this answers your question.