Important information: Ice king/queen/prince are rather not planned to be re-released in the future.
Relying on information from community manager ROMI. It‘s the game designers‘ decision to make, not hers. I‘m thankful for the info nevertheless to reduce needless hoping and waiting.
So unfortunately it doesn’t look good for the fans of this events. They are treated as a one time special I think.
Ice marquess was not mentioned specifically but I guess that includes her as well. My personal guess only.