Hey guys, for everyone who want this to work on Linux servers: I went through the troubles of reimplementing the inidbi2.dll extension in C++: https://github.com/cmd-johnson/inidbi2-linux/
Just add @inidbi2 as usual, place the inidbi2.so inside the @inidbi2 folder and rename the "Addons" directory to "addons" (the Arma 3 server on Linux doesn't like the uppercase Addons folder).
That's it!
Running fine on my own Linux powered server for about a day now.
It's a quick & dirty implementation, but it works. Also it's the first extension I ever implemented. Please open up an issue on GitHub if you find anything missing / not working as expected.