Linfel's group knew nothing about the war situation. They arrived at the northwest border of the Xanzion Country, shared with Lergen. As one would expect, the border roads were closed due to the war. Nonetheless, the security wasn't all that tight since Xanzion wasn't expecting an attack from Lergen anyway.
By now, they had already passed Cinxeti City as they had agreed previously. They acquired a few civilian clothes and got rid of the Xanzion Army Uniforms. After resting and filling their bellies, they left and made their way to the border. Finally, they ignored the roads and crossed the border without being seen.
Lergen wasn't part of the alliance attacking Heffal, so there wasn't a need to hide their identities there. Plenty of residents from Heffal ended up trapped in Lergen exactly because they couldn't make their way back home. That helped as Vera and the others simply pretended to be a few more of these same residents.