As mentioned in my post the deceased is one of a series who have been given the name. According to other news sources they've already got another one lined up.
They had been using albino groundhogs for "Willie", so they were trying to source another albino. They had no luck on that so they now have a normal brown one to use next year. I suspect the delay in announcing the death had to do with frantically searching for another albino before giving up on finding one that matched the previous.