How to set the number of badges to display

wpDiscuz doesn't control the number of badges. It just gets the badges via the myCRED plugin hooks. You should check and see if myCRED has such an option.

Alternative: you can use the CSS code:

#wpdcom .wpdiscuz-mycred-badges-wrap .col-xs-12 .the-badge{
    display:none;
}
#wpdcom .wpdiscuz-mycred-badges-wrap .col-xs-12 .the-badge:first-child, #wpdcom .wpdiscuz-mycred-badges-wrap .col-xs-12 .the-badge:nth-child(2){
    display:block !important ;
}

This is just an example.

You can for example leave the third child. 

The topic has been moved to the correct forum.