While he was at Betong after this expedition, the Charles Brooke called on Chief Bunyau Apai Bakir and his brother Maoh at Rantau Anak to persuade them to submit to the White Rajah's rule. These brothers then consulted their Malay neighbours under Datu Patinggi Udin who obliged as they were the minority. In return, the Tuan Muda built a fort at Munggu Senggang, Betong complete with cannons and under their combined charge. This fort aimed to prevent Rentap's allies going out into the South China Sea via Batang Saribas river and attacking people along the coast as in the past especially under OKP Dana Bayang.