My experience has been that Clerk Support is usually rather reluctant to do this for anyone except the bishop/branch president because they are the only ones the Clerk Support really has ways of verifiying their identity over the phone before handing out confidential information. Not that it happens regularly, but theoretically anyone could call in and pose as a ward clerk or counselor in the bishopric in an attempt to get identifying information about someone else.
So be prepared to have your bishop make the call.
As an alternative, I would try to think of other places the member might be listed. For example, if the spouse, either parent, or any of the children are members, she might be listed on their membership record, and you might be able to track down her membership record that way regardless of spelling and birth dates.
And speaking of birth dates, I'm sure you are aware that most of the world and the Church use a
Little Endian date format, whereas the United States generally uses a
Middle Endian date format. This means that if the paperwork for this member was filled out by someone from the United States, and the numbers are ambiguous, 10/09/1970 could mean either October 9th (middle endian) or September 10th (little endian). An example of an unambiguous date would be 13/10/1970 because there is no 13th month, thus you know that date is listed in little endian format.
If she happens to have a temple recommend, her membership number should be hand-written on it.
It is possible that even though she was baptised and confirmed, the paperwork to record those ordinances was never generated or processed. Thus you might end up having to go through the process of getting witnesses to testify that the ordinances were perfiormed (your bishop can get instructions on how to do this from the CHI), or as a last resort perform the ordinaces again.
