I was checking out this plugin in test install when I saw that in addition to the donate info in the plugin's options page which was cool, there was also 600px x 500px widget to donate to plugin author in the admin dashboard as well which is not cool at all. In addition, since I activated it Network-wide, the donate widget box was in all dashboards of subsites. The big widget in dashboards is not only seen by the Super Admin but for all other user role levels as well.
I've since deleted the plugin from test install. Those huge dashboard prompts are, in many ways, as intrusive and obtrusive than other plugins which have been removed from the WP repo have been.
At the end of the that donate widget in dashboard, there's a line
After donation you will possibly get to know how you can hide this notice easily
I don't know how much you have to donate to hide the eyesore, but at a glance - haven't tested it - you can "hide" the prompt by deleting the following lines in the plugin's donate.php:
Add_Action('wp_dashboard_setup', Array($this, 'register_widget'));
<div style="max-width:600px"><?php do_action('donation_message') ?></div>