Found on the Zanzibar government web page, a photo from the House of Representatives of Zanzibar with, on the table in front of the panel, two flags. The one on the right is quartered (clockwise) in red, white, green and white. There is no fringe but an emblem. The emblem seems to be party per fess sinople and gules. On the sinople (green) part a white lettering (party's abbreviations: CPA) and on gules a golden St. Andrew.
This is the flag of THE COMMONWEALTH PARLIAMENTARY ASSOCIATION. Tanzania is part of the British Commonwealth and I believe the CPA sponsored the event in Zanzibar where this flag was shown. This link will take you to a page that shows a man seated in front of a full size CPA flag.
Mr Barghash's reference to the Norfolk Island page is very useful, for it shows that the symbol on the CPA flag is actually crossed sceptres rather than the simple saltire which was all Manuel could show on his gif of the UFE. See also this webpage, though the sceptres on the flag are gold rather than green.