Technically the best case scenario would be to get full mirror control (up - down - left - right) but without the 'memory' option as the lack of wires coming from this 5-pin mirror doesn't have the additional 4-pins needed to read the mirror position for the memory function.
So it is your call on what you want to do. Full function without memory or get another 9-pin mirror.
Sucks you ran into this road block. Good luck!
2004 BMW 330Ci Convertible