I wrote a post in the Book of Ana Karithon, in defense of the designers with regard to Ana Karithon's power, Protection from Evil. This power, unfortunately, ignore Valkrill's units.
While this is a terrible development, the designers were probably not allowed to know that they were even getting another general, let alone one that was "evil," at the time they designed the D&D Master Set. Therefore, they missed the chance to include Valkrill, but not because they dropped the ball, but because WotC threw them a bit of a curve. At least, that's how I see it.

A non-rep signer (though he was kind enough to give positive rep) sent me this message:

"If you think it's just like any other game, then you cannot possibly understand what it means to a heroscape fan. Besides, you wouldn't be so forgiving if an average site member had made such a mistake. Is everyone here at this sitea a kiss@ss?"

My response it this: If anyone, a designer or otherwise, made a unit now that didn't take Valkrill into account in such a manner, I would call them on it. If a custom unit creation, made a year ago, didn't include Valkrill, I would not penalize them later. I would, in fact, be just as forgiving. I am not kissing ass.