In the Song of Solomon Chapter 5, a woman is describing a man, a man who has not yet been born. In other words, a prophecy is being uttered. In verse 16 of Chapter 5, it says, “His mouth is sweetness itself; he is wholly desirable. This is my beloved, and this is my friend, O daughters of Jerusalem.” It is hard to say for sure if each word is accurate, because if you visit different websites, on one they will say beloved, on another they will say lover, etc. As we can see even from this example, a slight change in the word can change the entire meaning of it within the context of individual people's experience.
The specific word that excites the controversy relevant to this particular scripture is mahamaddim. I have read that it means delightful, lovely, etc. So there is apparently in Hebrew more than one word that has the same root. It does not necessarily mean the Prophet Muhammad is being discussed, because in other contexts in the Hebrew scriptures, there are words with the same root as mahamaddim where it would not be possible for Muhammad to be referred to, as the person under discussion is actually a woman.
One thing I do remember is that when I was a Mormon, I remember hearing or reading that the Song of Solomon was not canonized scripture. In other words, it was not a reliable part of the Old Testament and should not be considered doctrine.
To be honest, I never know what to think about when people point to Hebrew or Greek words to try to prove a point they are making about the Bible. I don't have any firsthand knowledge of these languages, so I have to take what people say on faith when they are doing such translations. However, they often do give food for thought, and I am a curious, open-minded person. I was surprised that there is such a clear explanation about this; I was expecting far more ambiguity. It seems like common sense that it was not the Prophet Muhammad who was being discussed but I invite everyone to look at these websites themselves and make their own decision.