See http://musicbrainz.org/edit/26569814 - http://beta.musicbrainz.org/edit/26569814 does work fine though, so there might be nothing to fix.
FWIW, this is one of the beta-entered release merge edits that gave an error (but not an ISE) in non-beta before the last release.
Internal error when getting edit #26614765
Internal server error trying to view edit history
Internal Server Error when browsing edits