The data currently in IPUMS Terra are tabulated from IPUMS International microdata, and therefore rely on the geographic codes present in the microdata. Due to restrictions to protect confidentiality, microdata geographic codes must not identify areas with populations less than 20,000 people. As a general rule, we provide geographic codes for first and second level administrative units for most countries.
We are working on a new project assembling published aggregate data from around the world, including the village level data you mentioned from Bangladesh. (We were actually looking at some of those tables this week!) However, we are probably still a year or two away from being ready to disseminate data from that project.