Hello,
I see, thanks for the clarification! There isn't a way to use the Buttonizer positioning parameters to do that. You can try accomplishing the same thing by adding a custom class to each button group, then add some CSS to customize the appearance though.
If you look on the right rail for each button group and scroll down, there is a tab to add a custom ID/Class:
If you click into that tab, you can add a custom class. For example, you can add whatsapp-group and callus-group for the respective button groups:
Once you have given each button group a custom class, you can add some CSS to your site to adjust the appearance. You can start with something like this for example, and adjust from there:
.whatsapp-group, .callus-group { width: 50%; }
Hope that helps!