You don't have to edit or remake the DLL at all. It's set up to be much easier to customize than that (not my doing, but nice anyway).
First, download the Genius YML file from github
. It's in the "Configs" folder.
Then, I guess, rename it to whatever you want (don't know if this is necessary).
Then open it in any text editor.
Change the name field from "Genius" to something like "Genius (with pointless non-standard section headers)"
so you'll know it is different when you see it in MB.
Delete that line from above from the "post-filter" section and save the file.
Put the YML file in \%AppData%\Roaming\MusicBee\mb_LyricsReloaded\providers
Relaunch MB, and you're set. Deselect the built-in Genius and activate your custom version.
A smile is happiness you'll find right under your nose.