Custom AABBs on MultiMesh causing mesh distortion (imported Mesh, Mobile Renderer)

[Bimbam360]

Tested versions

v4.3.dev4.official [df78c06]

System information

Godot v4.3.dev4 - Windows 10.0.22000 - Vulkan (Mobile)

Issue description

I just tried applying #79833 in 4.3dev4 to my mobile project and get the following behaviour with a basic imported mesh:

Base and when set to (-1000, -1000, -1000, 2000, 2000, 2000) manually in inspector

When set in GDScript prior to (or after) adding to the scene with MM.custom_aabb = AABB(Vector3(-1000, -1000, -1000), Vector3(2000, 2000, 2000))

Steps to reproduce

Load and run the MRP
Toggle comment 'MM.custom_aabb = AABB(Vector3(-1000, -1000, -1000), Vector3(2000, 2000, 2000))' and run again.

Minimal reproduction project (MRP)

MRP_Cubes.zip

[maidopi-usagi]

Tested the MRP, and I think it may be related to the strategy of mesh LOD picking, as disabling LOD generation in the import settings seems work right.