shri swaminarayan bhagwan is a reincarnation of lord shri krishna at his own free will.
it does not mean that because there is nothing in the scriptures about lord shri swaminarayan that he is not god
lord krishna has himself said that
"whenever and whereever there is a decline in religious practice and wicked actions predominate, i descend myself and assume a form"
"in order to protect the saints and to destroy and annihilate the devils and to establish the principles of religion, i advent myself and come into concrete existence from time to time"
therefore there is no difference between ram, krishna, and swaminarayan as they are all one supreme being