The ChangeLog page of this plugin shows that its Max KS version is 7.5.1.
It seems that we can not use this plugin in the KS version 7.9.x or 8.x.x.
It seems that “Max KS Version” is not taken into account when you go through the installation process. You can install it. The installation seems succeed. But we get puzzled to find that plugins with Max KS Version < my KS version is not really operational. We do not find these plugins in the list of installed plugins. I have ever encountered a similar curiosity for jMeter-plugin:
I think that the plugin installation process should reject those plugins with Max KS version attribute < my KS version, so that users are notified of the restriction by Min & Max KS version.