Cooker uses steam in the main chamber for cooking but the steam is wood fired. It is legal. All this and more in the quick notes.
Doesn't say what contest the cooker was at or what contest (if any) the marking question was raised. But your BOD is making rulings as needed and I'm sure this will be in the rep advisories. I'd download a copy to your PDA/cell/crackberry device and take to contests or be old fashioned and print it out.