Hello, need some advice here so I can be sure when I book my ticket. Ive spoken to Etihad and Vietnam Airlines and getting conflicting information.

I want to travel on an etihad ticket from hanoi to london heathrow all the way. The ticket route is HAN - KUL - ABU - LHR. I am an etihad silver member so for an etihad economy ticket plus my silver membership I get 3 x 23kgs, total 69kgs as per their policy. Im taking a lot of baggage! My first leg (HAN - KUL) is a codeshare with vietnam airlines, and their economy baggage policy is only 30 kgs. What prevails? The etihad baggage policy for the route as per the ticket or the vietnam airlines leg?

Hopefully this makes sense, appreciate any advice. Thanks.