Board Thread:News and Announcements/@comment-4746796-20170324022701/@comment-26402117-20170327130439

I recall Wikia doesn't close wikis - but I think you can port the content over using Special:Export] here and Special:Import there (which keeps the edit summaries). And then you can ask them to merge the two into GDP by turning this wiki into a redirect so long as you link to (here?) where the community gave the okay.

If you've done stuff to the pages or templates to redirect them, you'll just have to undo that on the GDP page after you import it.