Gift to prophesy was NOT same as being a prophet, as that gift was not giving forth infallible doctrines or interpretations as she claimed to have!Well, great. You personally didn't make it up, but it's not biblical. That means it's pretty much the same as if you made it up.
Something about this premise smells fishy.
Yes, Ellen White said she had the gift of prophecy. No, she didn't "define doctrine." All Adventist doctrine is based on the Bible and that's why you never see anyone defending our doctrine based on what Ellen White said (unlike Catholics who appeal to their tradition to validate their extra biblical beliefs).
If you would pay attention to your own quote you'd see that the context indicates that the circumstance in question was how to correctly interpret "new doctrines" being "brought in" by "ministers and doctors." Those involved in this situation searched the Scriptures "with much prayer." Sometimes they would spend "whole nights ... devoted to searching the Scriptures." When was the last time you devoted a whole night to "searching the Scriptures"? Since the Roman Catholic Church devalues the Scriptures in favor of elevating its own contraflictory traditions then it's not likely that any emphasis is placed on reading the Scriptures. Wasn't it the RCC that forbade the translation of the Scripture so that the common person could read it for themselves? Um, yeah. After all if the people could read the Scriptures for themselves then they would see the heresy that the RCC was teaching and a reformation would likely take place. Oh wait ...
But for the grace of God go I,cyspark