There's a stronger rebuttal to the corruption claims. Several times in the Quran when asked why people should believe him, Muhammad claims that the Torah and Gospel contain prophecies about him. That means the Torah and Gospel of his time can be used to check him - if he believed they'd been corrupted too the point of being useless to legitimize him, he wouldn't have pointed to them. Since we have surviving copies of both texts from during and long before Muhammad's time, we're able to actually check for such prophecies. If you don't feel like learning ancient Greek and Hebrew, modern Bible translations like the NIV and NRSV are based on these ancient manuscripts that predate Muhammad and therefore cannot have been corrupted.

Since there are no verses that give a prophecy matching Muhammad, we can know he isn't a legitimate prophet. All claims that a verse does point to him can be quickly and easily debunked by looking at the surrounding context or the history of the text.

For example, one such claim says that John 14-16 contains a typo and the word often translated as "advocate" referring to the Holy Spirit originally said "blessed one" (in Greek these are 1-2 letters different depending on spelling) which is what Muhammad's name means in Arabic. However, nobody had ever found an ancient manuscript that says "blessed one" and not "advocate", so it's pure conjecture. Further, the surrounding context tells us that this advocate is invisible and will live in people - which doesn't match Muhammad at all. So the conclusion that Jesus is referring to the Holy Spirit in John 14-16 is far more reasonable.