I am not able to locate the MediaWiki option in the Export menu. I have double checked that the plugin is activated in my digiKam settings.

How can I debug this issue?

I am using Kubuntu 14.04
digiKam 3.5.0
KDE Development Platform 4.13.0
Kipi plugins 3.5.0
LibKipi 2.1.0

check your ~/.kde/digikamrc file and make sure in section [KIPI/EnabledPlugin] there is a line MediaWiki Export=true

make sure there's a package called something like libmediawiki or libmediawiki1 installed

make sure that your kipi-plugins package includes and installed file kipiplugin_wikimedia.so

test as as new user