if the first switch is off, half speed crystal is not connected, so only regular is set
if the first switch is on ,half speed crystal is short circuit, you have the same connection between the two legs of the crystal.
so will be the same if the first switch is on or off
Here is something that I don't know, if you can put crystals in parallel, in that case your switch could work, but will wait for some one else answer.
For the second switch, as I can see on the manual, one leg of the pitch bend goes to GND, the other to +Vcc (+3~6v), and the other to the on/off switch and then to one leg of the original crystal on the board, in that case you don't need to take out the original crystal. But have the same question as before here... if I can put in parallel crystals?