Because I'm very bored at work today, I've been following the voluminous Twitter posts about this incident.
Actually, there was some concern for the dog's welfare, although it wasn't directly addressed by the rescue organization's very terse statement. Amy Cooper had a media account in her dog's name and had posted about his life. There was more than one posting about the dog having "accidents" -- from choking to torn nail and fights in a dog park -- that triggered Twitter commentary of a doggy version of Munchausen by proxy. Difficult to say if there's any truth to that assessment, but given her very erratic behavior in the video, not to mention that she'll be very shortly unemployed, finding a new and stable home may be best.
For what it's worth, she was identified by two people who used to walk her dog. Both described her as neurotic and odd. Again, not necessarily a substantiation that she abused the dog, but apparently enough to trigger concern from the rescue group. I'm glad Cooper voluntarily gave up the dog. Her life is going to be very stressful in the next coming months as it is. Better to err on the side of safety if there are decent rehoming options.