Hi,

"So I installed it via sudo apt-get install libsdl-perl"

It looks like you may have installed the module into the library space for a different perl than you are using in your script (although your demo code showing how you got the version does not show the perl used). Installing via apt-get will put the modules in the right place for the system perl, which you may not be (and are recommended not to be) using for your development work. Check your @INC.

Hope this helps!