Why are there two versions of Sojourner’s speech?

The original was delivered by Sojourner and transcribed by Marius Robinson, a journalist, who was in the audience at the Woman's Rights Convention in Akron, Ohio on May 29, 1851.  And Gage’s version is  written 12 years later and published in 1863,  The full text of each version follows the synopsis below so you can see the differences line by line. I have highlighted overt similarities between the two versions. While Frances Gage changed most of Sojourner’s words and falsely attributed a southern slave dialect to Sojourner’s 1863 version, it is clear the origin of Gage's speech comes from Sojourner's original 1851 speech. It is interesting to note that Marius Robinson and Sojourner Truth were good friends and it was documented that they went over his transcription of her speech before he published it. One could infer from this pre printing meeting, that even if he did not capture every word she said,  that she must have blessed his transcription and given