Sorry for this issue, I didn't think about testing that patch in a running instance to verify.
I think Jenkins is simply looking at the dependencies first, and then our plugin classes. As it finds that class in the dependencies (Zeppelin JAR), it doesn't bother loading our special class.
Loghi Perinpanayagam see: https://www.jenkins.io/doc/developer/plugin-development/dependencies-and-class-loading/#pluginfirstclassloader-and-its-discontents
I think with that fix it should work. But testing it requires you to `mvn clean install`, then copy the `.hpi`, install a local Jenkins (e.g. download latest LTS version, then run something like `JENKINS_HOME=/tmp java -jar jenkins.war`) and install the plugin manually to verify it works.
If so, then cut a new 1.0.1 I think. Let me know if that works.