I think you are right. I guess my theory was based on some pre-conceived notion that was not entirely accurate. Wikipedia does say:
>The Andaman and Nicobar Islands of India are geographically considered part of Maritime Southeast Asia. Eastern Bangladesh and Northeast India have strong cultural ties with Southeast Asia and sometimes considered both South Asian and Southeast Asian.
>The Andaman and Nicobar Islands of India are geographically considered part of Maritime Southeast Asia. Eastern Bangladesh and Northeast India have strong cultural ties with Southeast Asia and sometimes considered both South Asian and Southeast Asian.