Two resource UUID for same artifact?

What you are seeing is module-specific artifact. All module-specific artifacts have a corresponding base artifact. If you check the XML data returned from https://<server>/rm/publish/resources?resourceURI=<resourceUUID>, "about" property (under contextBinding) provides URL information about the artifact version included in the module and "core" property provides URI information about the base artifact.

If the artifact also resides in a module this is normal.
But then you would expect for example, https://<server>/rm/resources/<resourceUUID_1> to open the core artifact outside the module, and https://<server>/rm/resources/<resourceUUID_2> to open the artifact inside a module.

Is this what you're seeing?