static textbox have the handle name as handle.text, handle.text1, handle.text2 etc..
so first you need to check what is the name of your static text
type GUIDE command in the command window, then click on tab "open existing GUI", then select your .fig file
Once your file opened into editable mode, just double click on text box. It will open all property values of that text box.
Check for proprty TAG, what is the value. It should text or text1 or text2 etc etc..
Now let consider it is "text1"
so "get(handles.text1,'String')" will give you the value(name) of text for your static textbox.