When using the github pull request functionality in SonarCoud, SonarCloud will only report as a github status and comment on a pr if the sonar.pullrequest.github.token.secured property is set using the UI, not during the mvn sonar:sonar command (I am not using Jenkins). I have a lot of repositories and it would be much more useful if this could be sent via code instead of having to manually setup the repositories.
Should this be a feature suggestion @ [Deprecated] Suggest new features instead ? Seems like current behaviour, more than a bug per-se. And it would be interesting to detail the use-case in more length, because that I might open up other solutions the the one you mention (e.g. if the token is valid for multiple projects, than an organization-wide settings in :sonarcloud: could maybe help).