Unreal GLTF Export at runtime not exporting material textures. UE 5.2

I'm having trouble getting unreal to export a GLTF model and for it to keep the textures used in the materials it exports. The actual model export is fine, and it's correctly creating the file with the materials that are assigned to the mesh, but the materials don't contain textures, they are being exported as simple colour textures when I import the GLTF into blender.

Screenshots of unreal/blender [here](https://imgur.com/a/xxny4vo). Working in UE 5.2, but can version up if that will help.

I've found [this page](https://dev.epicgames.com/documentation/de-de/unreal-engine/exporting-unreal-engine-content-to-gltf#textureoptions) in the unreal documentation, and tried variations and combinations of:

* bake material inputs * texture image format * export texture transforms * export unlit materials (even though it's a default lit material)

Along with a few other options, but i've not found a combination that works to export the texture in the material. The closest I can find to someone saying it works is [this post](https://forums.unrealengine.com/t/low-resolution-exports-for-gltf-files/647180) where someone has issue with the exported resolution (so it clearly *works*), and i've based export options off of that post, but that doesn't work for me.

Does anyone know where or what i'm doing wrong? I can share the assets if needed, nothing worth protecting.