In 1970, the Groffs moved to Chatham, N.J. and were accepted as missionaries with TWR. They have served primarily in the Head Office, except for a period during the 1970s when they went to Guam to locate property and establish TWR's first AM station. The Groffs came back to headquarters after a year and then returned to Guam to oversee the establishment  of TWR’s shortwave station.

When they returned to the U.S., Rodger looked after headquarters services, and Brownie helped in the donor relations department. In 1994, the Groffs retired from TWR. Rodger went home to be with the Lord February 10, 2016.