Recurrent
I think Flight Safety had a New York based flight dispatcher course running, perhaps do a search and get their contact details and ask them if they still have a dispatcher course and if they can do recurrent.
The problem is that if they do, they may not want to run it for just one person unless others were interested.
If you intend to go back to work as a dispatcher you will need to undergo company specific initial training which will take care of your recurrency issue. If a dispatcher has not undergone recurrency within 24months they have to go back and do initial anyway.
May I suggest sending your query as a private message to a longstanding member of PPRune and goldmine of info on all things dispatcher, his name is NoSig.
I think he would have a good idea of what you should do.
All the best.