There is not a way to render it in this way, however there are a couple of possible workarounds.

The first one is using CSS to rework the layout using floating boxes as below:

#jmap_sitemap div.jmapcolumn>ul {
width: 100% !important;
}
#jmap_sitemap ul.treeview>li>ul>li {
float: left;
margin: 10px;
}

The second one is creating additional and multiple menu with alias menu items poiting to the main menu and use them in the sitemap to have multiple menus and columns.

By default Joomla menu are synced automatically and can't be duplicated.

Cheers,
John