Christ taught there was but one Way, but he didn't rule out the existence of other guides to that Way.
Uhhhm....are you sure?
"Jesus said to him, “I am the way, and the truth, and the life; no one comes to the Father but through Me."
And, following John 3:16 (the most famous verse in the whole Bible), The Bible goes on to say:
Anyone who believes in him is not condemned, but anyone who does not believe is already condemned, because he has not believed in the name of the one and only Son of God.
Why is it that exclusivists tend to ignore John 3:17?
For God did not send the Son into the world to judge the world, but that the world might be saved through Him.
(my preference for the NASB is simply because it's one of the more readible of the translations that places a priority on word-for-word translation.)
The Incarnation of Christ in human form was intended to save humanity, not condemn it. Christ is an embodiment of the Way. But not the only lodging of it.
In My Father’s house are many dwelling places; if it were not so, I would have told you;
So, if you reject the Way, you reject Christ, even if you claim to venerate his name.
See Matthew 25:31-46, and hopefully you won't end up as one of the foolish goats who thought Christ is some remote potentate who vainly cares only about his name, but instead be one of the shepherd's wise sheep who realized he cares about his message as well as all his sheep, not just those who bleat his name with vain repetitions.