The way RealityComposer handles texture files clashes with the way, rapidCompact stores them in USDZs.
If more than one USDZ uses ./foo.png, only the first occurrence of foo.png will be stored and other USDZs referencing to that first PNG will look weird.
This strategy is to reduce total file size on export if several embedded USDZ use the same texture files.
The way, Apple handles this is NOT by comparing textures for exact match, but by preparing all involved USDZs in a single session of RealityComposer. RComposer will then store textures for the first Asset as 0/foo.png and successor as 1/foo.png 2/foo.png etc.
This very primitive way avoids name clashes.
I suggest you add a numeric field (default 0) to your platform we could use to manually type in the pathname prefix and you use it to store textures in subdirectories.
If you do so, please also add an (i) to explain its purpose.