Does Hyatt not give previous globs a soft landing to Explorist? In any case, if they are already a glob they need not retain Explorist to maintain their MGM Gold. In fact, they ought to be able to maintain Explorist by matching back from Gold. Which means we are all probably burying the lead here.
OP, you can match to MGM Gold if you haven't done so already, and then match back to Hyatt Explorist without ever staying another night if you don't want to. But remember, matching will not give you any milestone awards.