Correct. In the 1990s Exxon Exploration Company (EEC) was located in an office complex in the Greenspoint neighborhood of Houston which housed the technical staff responsible evaluating offshore and deepwater petroleum prospects in Nigeria, Angola, Brazil, deepwater Gulf of Mexico, Trinidad and Tobago, etc.
This may shock and amaze you, but in the late 20th century you could evaluate digital 3-D seismic data and digital well log data from the comfort of an air conditioned office in Houston Texas. You didn't have to do it from Lagos Nigeria.
AFAIK, The Exxon affiliate offices located in Africa mostly dealt with production, pipeline, drilling, and engineering issues.