Regarding a multi-row header w/ colspan
From the official forum:
Multirow headers will be available in the Pivot Grid, which we are currently developing with the idea of releasing it for Q2 2014. We may port the implementation for the standard Grid for subsequent releases, but I am afraid I can't provide official information about the timing and probability at this point.
http://www.telerik.com/forums/multiple-header-rows
http://www.telerik.com/support/whats-new/kendo-ui/road
If anyone cares this is how we overcame the problem using slick grid. We are updating to kendo so we will just carry this forward until we have a grid that has these capabilties. We used a legend and then applied a CSS to each header