Hah, sorry. I'm better at replying to emails than to my notifications here.
While those skins do look cool, and would be pretty good for the undead summoned by Kain or Dustwalker, they don't look 'right' for the Tirthandaran Minions that Kitharsis creates. Implementing it so that those two unit types use different skins would be possible, but would require more models to be extracted/imported and thus would make the campaign even bigger.
Besides, I've tried to avoid using any resources made by other people - I primarly tried to use only the stuff included in Warcraft III or skins/models I edited myself.
I've tried to avoid using external resources (such as skins) as much as possible in TTBE.