I doubt it was the campaign. If it was, they would crow about the endorsement officially. Not their MO.
There is nothing to prevent anyone on social media from starting a rumor. Any one of 320 million Americans could go out there and start a rumor about anything. Sounds like a ‘rat op dirty trick to me. If you have a chance, look up LBJ’s political dirty tricks. Particularly the one about the pig farmer.
I'm certain it wasn't the Trump; Team!