I don't really follow what you are doing. I get the impression you are using VA Outline to move the implementation, and that you are doing this in the cpp file.
However my cpp files, even when I have to classes, look like this:
void CFoo::method1() { /* ... */ }
void CFoo::method2() { /* ... */ }
void CBar::method1() { /* ... */ }
void CBar::method2() { /* ... */ }
when the code is organised like this moving the function implementations around in the file does not move them from one class to another.
Currently VA Outline is not designed to update two different files in one go. Assuming your code is split between a header file and a cpp file then this would be required.
Moving a function from one class to another class is an interesting refactoring operation, but is not quite what VA Outline is designed to do.
How a "move function from class A to class B" should work would need a little bit of thought.