I've worked in an animal rescue/rehoming centre. The turnover for adopted cats was about three weeks i.e. that was the longest a healthy cat would wait to be rehomed/adopted.
As a volunteer it was my job to clean their pens every day then brush and comb the cats if required. Basically, present the cats and the rehoming centre to prospective adopters.
There was an adoption fee to be paid for each cat by the new owners which they did willingly.
There were also dogs to be rehomed. They had a larger out door pen to run in which had new, fresh wood pulp delivered regularly i.e. when they had flattened the shredded softwood from the running about. They slept in a comfortable kennel every night. Again, it didn't take long for a new owner to turn up and adopt them.
I'm aghast/open mouthed at the shit being thrown at the OP. If a child needed to be removed due to their needs not being met well that would be all well and good.
Do that to a dog and there's five pages of utter c*ery going on.
A pp pointed out it's a dog that is used to a family environment. At the age of six it's, ok not young but not old either.
Could the OP contact the rehoming centre in a couple of weeks' time and ask if Fluffy got a new home ?
(We had to re-home a cat because we were moving overseas. We gave him to a couple who are as soft as butter and dotty about cats. The cat would have been anxious with the new owners until about breakfast on the second day. When he realised he was on a good billet with them he would probably think, 'you mean I could have had this all along ?'
Oh yeah, btw, when horses get sold, for whatever reason there's not all this shit thrown at the old owner, is there ?