As found on Centos 9 stream discussion and original bug on RHEL 9.1, I encounter the same issue on Fedora 37.
Bug reported in 2136212 – Current libsepol 3.4-1.1 version issue with SEuser defintions within policy modules affects version 3.4-3 of libsepol shipped with Fedora 37 release.
A fix was published on May 15 2022 and merged on the master branch of libsepol.
This issue prevents SELinux policy modules which include SEuser definitions in their code to be compiled and loaded.
Such module is rejected by the libsepol with error message:
libsepol.validate_user_datum: Invalid user datum
libsepol.validate_datum_array_entries: Invalid datum array entries
libsepol.validate_policydb: Invalid policydb