As Panos has pointed out, your 'problem' is with the style!
The MAIN D variation starts at measure 45. There is a program change at the beginning of the bar which sets the Phr1 voice to the XG-Distortion Guitar, but then this event is immediately followed by another program change which selects the XG-StringEnsemble for the Phr1 part! This voice is then used for that variation.
You can simply edit the style to remove the second program change using MixMaster, or add yet another program change to select the guitar again using the Style Creator in conjunction with the Mixing Console, but even if you do this, the note pattern for Phr1 in Main D is just a three note chord sustained for 8 beats (which is the length of the Main D section), and this is much more typical of a part for stings than a guitar!
So you would probably need to use a different note pattern for the Phr1 part if you change the voice back to a guitar!
The style that you posted has the volume level for the strings quite low (32) but your registration increases it to 100 which makes the string sound much more noticeable! You might find that you can live with the style as it is, using the string voice, if you reduce the part level in the registration memory that selects Main D but that would also reduce the Phr1 level in the Intro!
If you want different part levels for the Intro and Main D, you would need to use two registrations. If you only want to use one reg. then you would need to modify the strings level in the style variation, either by reducing the note velocities or adding an expression event. You will need to do in MixMaster or some DAW since the keyboard's Style Creator (or whatever on Genos) will not allow you to access the style's Phr1 part unless you delete it and record your own!
Regards
Ian