Edible-nest Swiftlet

Hi,

Today I have a question for you all, and hope someone can enlighten me. Last week I visited Phu Quoc Island, and on one farm they had an open window in the top of a house. In the window a loudspeaker continously gave the sound of a swiftlet, and I saw one bird. If I understood my vietnamese guide correctly, they raised Edible-nest Swiftlets there (and my guide said they do the same near Nha Trang). However, my bird-book says the Edible-nest Swiftlet should not be found in Vietnam. Are they breeding Germain's Swiftlet and using the nest of that species for food like they do with the Edible-nest Swiftlet, or what?

I attach a picture of a Forest Wagtail that visited the area around my cottage for two days - a lovely guest.

Arild