He occupied the following positions: Executive Committee Vice President; Secretary for Swahili-speaking people at the North Shaba Annual Conference; General Board of Global Ministries Director; Interpreter at the 1992 General Conference in Louisville; Chairperson of the North Shaba Aviation Committee, Construction Committee, Ordained Ministry Committee; International Person in Mission in the country of Burundi (from 1993 on, he served as D.S., Supervisor, and Spiritual Coordinator for refugees).
He was the North Shaba delegation leader for the Central Conference at Wembo-Nyama. Bishop Ntambo planted about 157 churches in the region of Bukama and Lubudi. He opened two congregations in Nairobi. During his ministry he visited the following countries in order to fulfill his tasks: Zimbabwe, Kenya, Uganda, Tanzania, Somalia, Senegal, Zambia, U.S.A., Israel, Angola, Gambia, and South Africa.