Correct. SAM 6. 2 Beta 3 and NPM 11.5 Beta 4 are using different versions of Orion Core. SAM is the latest version, but NPM is not forward compatible with this later version of Orion Core. VMAN 6.2 and SRM 6.0 are the only other beta releases that are running the same version of Orion Core and QA validated to be compatible throughout the beta process.
If you uninstall NPM and re-run the Configuration Wizard does that resolve the issue? You may need to uninstall both SAM and NPM, re-install SAM, and then ensure you're starting with a new/fresh database when the Configuration Wizard runs.