you need to return the wires to their original positions with solder connections and shrink tube.
There are two wire coils in your fan unit. On low speed, one of the coils is energized. On high, both coils are energized.
A three position switch is not going to work. You definitely have power moving in the wrong direction, probably from the low supply wire to the high supply wire and have the ground terminal on the wrong pole of the switch. If this switch were installed as correctly as it could be (seeing that it's the wrong switch for this application) then the BEST that you could hope for is to toggle between each energized coil and achieve low speed in both positions.
It is INFINITELY better to diagnose and properly repair than it is to start hacking off connectors and installing shade-tree work-arounds. Ditch the switch and restore the wires and connectors to their original locations. We can then help you diagnose the problem. Please also provide pictures of your repair and connections.