Bluff

It would be weird that after five of Ge Liang's men saw Lan Zhang and Lan Wan with Si Ning and Song Feng just a hundred meters away from them, then they disappeared and spend time before finally showing up at the camp, it might raise suspicion if it was reported to Ge Liang so this gave Si Ning no choice than to hasten and conclude their plan with Lan Zhang and his men then they started heading down straight to Ge Liang's camp.