I attached the zip file.
Is the plugin in the Moodle directory ?
Could you post the patch the git of the author ?
If I've read correctly, it's support Moodle 2.4 ?
Maybe it's included in Moodle 3.x, now ?
At the end, I add no answer, only questions : )
But I'm also interested by the process to contribute to "wake up" (modernize, upgrade,...) abandoned plugin.
David Mudrák runs (or used to) an "adoption scheme" for plugins with no current maintainer, if you're willing to take over maintenance of the plugin. Another option is to create your own fork on GitHub or another git hosting site with your changes, and hope that they can be merged into the main plugin in the future.
As Mark mentions, we have a plugins adoption scheme. For further details, please see the dev docs Plugins adoption programme.
Additionnaly to what has already been wrote, you can read more information on the documentation about the plugin adoption program.
If you intend to regularly update a plugin, including for the latest (and supported) Moodle versions, don't hesitate to candidate for plugin adoption.
If you just want to make a one shot update of a plugin, you can create a discussion about it, in the General plugin forum (if no more specified), and write in the plugin's comments, linking to your discussion.
I tried to contact the plugin maintainer, but I think that it is an abandoned plugin
One of the maintainers seems to be an active user here at moodle.org. Have you tried to contact them both on their emails as well as via the moodle.org messaging? Have you reported the lack of recent versions as the plugin bug in its bugs repository? Or even submitted a pull request with an update?