I think u should do legally translate marriage certificate first. Its not take too long. Just a couple of days. And ur dtv process may take a weeks. Ur wife depemdent dtv visa can apply after u got dtv visa. So i think u have sufficient time to marriage certificate
The ask:thailand community, consisting of multiple Q/A groups with over 100,000 members, powers this platform. It is not an official government resource. Our members actively contribute to this resource, and while we strive for accuracy, we cannot guarantee its complete reliability. Assistance to travelers is provided as a community service.