How to run release:perform from a given Git tag?
This issue is filed as SCM-729, and currently unresolved. In the meantime, you might consider a workaround.
The simplest is to forget about maven-release-plugin; clone, check out that tag and then run mvn deploy.
Alternatively, you can use release:perform with a manually edited release.properties file. Set scm.tag and scm.url and then run release:perform.