Very interesting. I have never seen a servo setup like that in my life. But, the manual is saying 90*, so set it at 90*. It looks like one servo is doing the aileron and I have no clue on the other servos.
If this was my heli, would just use what they say to do in the manual. Afterall it is their heli.
And I'm not a futaba guy, so I don't have a clue about any of those settings either lmao.