Hello Troy Mumm

Megamenu will not be displayed on the offcanvas. This is the feature. So, you are doing all right here.

Best regards

I assume the "megamenu" wouldn't show on mobile, but shouldn't the level 2 submenu items show as usual? How are users supposed to navigate to these pages?

Please use this CSS to Template Options -> Custom Code -> Custom CSS

body.ltr .offcanvas-menu .offcanvas-inner ul.menu>li.menu-parent>.nav-header>.menu-toggler{
    right: 0px;
}