The “stable” releases are named “stable” in the sense of “not changing” and are not generally recommended if you are making changes like introducing new plugins. New plugin development generally is free to follow current development versions. New “stable” releases are done only a few times per year, and that would be handcuffs for work like this.
I do wish at this point that CDCK would drop the “beta” moniker from their rolling releases because it really isn’t a great description. It keeps introducing confusion like this, and creates mismatched expectations. But 3.4.0-beta is almost certainly what you’ll want to work with this plugin at least at this time.