I dont think it Shortcodes Ultimate for columns Tom. Have it on all sites I do, using your GP theme and child. And also on 2 Genesis websites.
Get this, I took out ALL WIDGETS of left/right area of this site, leaving only Footer widgets. After I reloaded homepage, 2 ARCHIVE widgets were at left and right. And also 2 search widgets above each Archive widget.
And I dont use either!!! Check out. http://dbsatucson.org/dbsa1.png
If you run your page through an HTML validator, you’ll see you have an opening element without a closing element somewhere on your page causing the HTML to break: https://validator.w3.org/