Traben

Can confirm for 1.20.

I have discovered the root cause accidentally while working on an unrelated minecraft mod.

This is a 1 line variable oversight in the static method that creates an EntityModel map that all models are loaded from.
Unlike every other armor model the "drowned_outer_armor" entry accidentally uses the model for "inner_armor" instead of the "outer_armor" model.

This isn't technically a rendering issue, it is correctly rendering the wrong model.

Minecraft Bedrock Version (win10) : 1.11.4
Logitech headset : G430

my situation reproduces the comment above exactly and has been the case for me for nearly 3 years