Custom model data is not applied to open bundle

When trying to use custom_model_data with a bundle, it only works for the base bundle model, but not for the two new open models, they do not use the specified custom_model_data component and always display the default model ignoring the model overrides.

Steps to Reproduce

1. Apply the attached example resource pack:

1. Give yourself a bundle with custom model data 1 (it will be completely invisible, except the storage progress bar)

   /give @s minecraft:bundle[minecraft:custom_model_data=1,bundle_contents=[{id:'diamond'},{id:'obsidian'}]]

Observed Behaviour

When scrolling or using hotbar keys to select a specific item inside the bundle, the bundle texture changes from the custom one (completely invisible in the example resource pack) to the default opened texture.

Expected Behaviour

The bundle should respect the custom_model_data and show an empty texture (only the selected item should be displayed), but the bundle front and back should be completely invisible (using the example resource pack).