I don't see that she is saying Jesus did not treat his disciples differently. That's not what the sentence you quote says. To "put on an equal footing" might involve elevating some, while lowering others, and perhaps leaving some where they were, which would be different treatment for each.  She also goes on to speak of the disciples  and their quite different and privileged relationship with Jesus, noting that they had the opportunity and humility to ask for explanation, and emphasizing the difference in their treatment in a manner that seems to harmonizes with your cited verses.