You do understand that it is the Biblical Jesus who says there is only one way, right?
mormonism has nothing to do with the Biblical Jesus.
And the real question is your interpretation of both “Biblical Jesus” and “Mormonism” accurate? Are they really mutually exclusive? What is included in the “modern Bible”, the King James, the Orthodox, the Holy Roman and many others may or may not be the way if we pick at their differences. I didn’t find the answer for me in the book of Mormon (a companion text to the Bible), but I didn’t find it to be anti-Christian either. Mormons are certainly not the first to want to apply their own flavor to the way.
As I have said before, Faith is not the problem; preachers on the other hand, I’m not so sure.
Christ paid in full for our sins. All we have to do is accept that gift from our Savior. The rest is how we feed that relationship. In the end it is what is in our hearts not the edicts or interpretations of a church that matters.