Hornets boss Ray Lewington is willing to let the pair leave on loan in a bid to get first-team football.
Midfield star Fisken has failed to make a single appearance all season, while defensive ace Doyley has been in and out of the side this term.
The Icelandic outfit were alerted to the duo's availability by former star and current Watford striker Heidar Helguson.
Helguson helped set up the moves and their arrivals will be a major boost to the Icelandic side.
