WotG Spoiler:
Jueno is only there to be involved with the storyline of the crystal war. It was closed to the public as it was beginning to surrender to Shadow Lord's army... The Shadow Lord Army lost that war and was the turning point in the war. Because of that loss, the beastmen then decided it would be best to divert their attention to Tavnazia and the Northlands.
More attention was brought to the Northlands and that battle than the battle on Tavnazia with the 4 nations because they felt that would cripple the shadow lord. Losing Tavnazia was, as I view it, a sacrifice madefor the greater good of the war.