Additionally, if you take this definition of a derivative work, I do not believe that an update of this nature counts as a derivative, because the goal is to create something that is virtually identical to the original. If you make the update and add, say, a ratio tweaker setting or fix a text typo, that would be a derivative work because you made a substantive or editorial change. Finally, an update like this is made in good faith, so as long as you link back to the original work, you pass the "don't be a d*ck" test.
https://commons.wikimedia.org/wiki/Commons:Derivative_works#What_is_a_derivative_work?
Therefore: if you don't want to publish the updated plugin for the community, I'm very comfortable doing so, but you figured out the update so it's your author credit to take.
