What if when you did temp custody you said that the person was a grandmother when really she is the aunt does it still make the temp custody legal?

The reason it would be challenged is because the court must have a clear understanding of the facts so that it can issue an appropriate order.  If those facts are incorrect, that error should be brought to the court's attention to determine whether the Order should change. However, if the only difference is the biological relationship, that may not mean the Order has to change.  The issue is what is in the best interests of the child.  If that best interest is having custody with the aunt, the court could certainly order that on a temporary basis.