This global rename is stuck "in progress" as of 28th Feb. on wikidatawiki. Edits there are not that high, but overall the user had more than 100,000 global edits.
Unbreak Now because of the fact that the user is unable to use their account until the rename fully finishes, in accordance to the Wikimedia-Site-requests project triaging rules. Feel free to decrease to High if you feel it is more appropriate though.
Addendum: issue has been raised at idwiki.