"dak bungalow" is an old or dialect word meaning a posthouse of the old indian postal service (dak), used as lodging by itinerant british officials and other travellers and as a make-shift courthouse in rural areas. If your teen uses it, they have most likely picked it up from a book, video game, period drama, or a regional grandparent rather than a modern peer group. There is no cause for concern here; the word is largely out of contemporary teen usage. If it appears in a school text, it is being studied for vocabulary or historical context. You can treat it like any other archaic vocabulary item.