What do we think is going on in German held Vietnam?

In Kaiserreich, Germany has taken over Vietnam from the French. Ho Chi Minh, OTL the leader of the Vietnam communist-independence movement, is himself is in France as of 1936.

Presumably the native Vietnamese are not thrilled to be traded from one European power to another, as by the 1920s there already a well-established Independence movement, which had already launched a major rebellion in the 1880s. In fact Vietnam leaders petitioned at the 1919 peace talks for Vietnamese independence, but Woodrow Wilson was unswayed by their pleas.

Transitioning from French to German rule wouldn't have been smooth. It seems the French had setup French language schools for the upper tier of Vietnamese society, and French was the language of governance and trade. Also, Catholicism seemed to have made strong inroads to Vietnam, and now they're under the Protestant Germans.

What do we think the Germans see as the purpose of Vietnam? As one big naval base to watch over China? As an economic colony to exploit? As militarily and industrially necessary because it's a source of rubber?

In OTL, the French seemed to invest quite heavily in Vietnam (IndoChina) once they realised how resource rich the region was. They made Saigon a port to contend with Singapore and contest it's power.

Would the Germans (pre-Black Monday) have been as equally keen to invest, or will their focus be elsewhere?

In general, what does Vietnam/Indochina mean to Germany?