I don't know where to look in the code that requires you to use the string "Timeless Isle", but here's some suggestions.
Lua Code:
-- prints "Timeless Isle" twice
-- regardless of locale, as the game translates
-- automatically and correctly
-- would output "Zeitlose Insel" for deDE
print(GetMapNameByID(951))
local Timeless_Isle = GetMapNameByID(951)
print(Timeless_Isle)