Despite the supposed mystery of where Fez comes from, I think it was given away in this episode.
It's clear that Fez is from Central or South America, and looking at Wikepedia for countries in these regions that where both English and Dutch colonies, there is only one:
Fez is from Guyana!!!!
"...The Dutch West Indian Company built a fort in 1616 on the Essequibo River. The Dutch traded with the Indian peoples and, as in Suriname, established sugar plantations worked by African slaves. While the coast remained under Dutch control, the English established plantations west of the Suriname River. Conflict between the two countries meant parts of the region changed hands a number of times, but by 1796 Britain had control of the region. The Netherlands ceded the colonies of Essequibo, Demerara, and Berbice to Britain in 1814."