I think it's unlikely that any animals at the Franklin Park Zoo were ever going to be euthanized. And it's likely the Zoo has made a long-term enemy of the Governor by publicly embarrassing him.
But as bare knuckle politics/public relations, they really did a tune on him. They mentioned the possibility, threw it at the Herald and let them make it sound as if they needles were being filled and the Gorillas were having their arms tied off.
Who wasn't sympathetic to the animals when they read the stories? I'm sure most are like me. I like Monkeys.