Empty Cells from XML, Not Sure Why?

I’m trying to set up a demo of dhtmlxGrid on Plunkr, but for some reason the cells from the xml file are not being read. It does, however, read the rows. This is the first time I’m playing with this dhtmlx, can anyone give me a hint of what I’m doing wrong or why it’s not working? Thanks!

Plunkr: plnkr.co/edit/rQuCXZsQ0VphJXGg3mks?p=preview


In your index.html there is a typo.
Instead of:

try to type: