I had seen this story before. Shortly after I saw it I visited my mother-in-law who had that very same or similar toy for her dog. I could create a suction on my hand with it. I suggested she throw it away, the dog would never know the difference. She thought I was being stupid and wouldn't, so I chucked it when I took the garbage out.
If I could get it to stick to my hand, I don't want to even imagine what it could do to a dog's tongue.