Why does TestComplete MSAA not seem to support error codes correctly?

Hi, we are currently trying to use MSAA in TestComplete to get the values from a list object in a GUI by first selecting it from the TC script and later reading the associated values.

To enable this, the programmer implemented the IAccessible::accSelect method for this object; but while this method has a return value of type HRESULT, TestComplete does not show any error value when this method is called from a script with parameters outside of the range of the list. The result shows up as "undefined".
Do you have any idea why this could be, or how we could get the correct error code as the return value for this operation?