The playback plays any bend larger than a whole step the same as the whole step bend (the half step bend is correct, though).
Likely this is happening because whole step bend is implemented as a full turn of the pitch bend wheel. However, many guitar virtual instruments allow you to customize the max bend distance. So, for this example, I could set the max bend distance to be 2 whole steps. What would be great is if I could tell Dorico about this, and it would adjust bends as such, for example, making whole step bend half a turn, 1 1/2 whole step bend 0.75 turn, etc.
No, not that I can think of, I’m afraid, because there’s no way to send the required system exclusive message that is needed to set the pitch bend range.