I did reproduce the PO upload scenario for VND PO resulting in 0 estimated landed cost and it does look like this is due to the local (VND) styles having the wrong purchasing type (RBG-P) in the style master or the style vendor master.
I updated all the VND styles and style vendors in BU 2 to have null in these respective fields; currency type, currency usage and purchasing type.
When you test, make sure there is no existing PO with the problem or this could still result in having 0 estimated landed cost.