There are cases of dogs buddying up with one or more dogs for days at a time, and dogs being drawn into proximity to each other by food sources, however none of the above populations form packs the way wolves do
I'm liking the scientific term "buddying up". There is plenty of evidence of feral dogs forming packs, if there is also evidence of feral dogs living solitary lives, then that is highly likely to be the effect of human influence, ie, humans are unlikely to allow dogs to form hunting packs in the same way as wolves do. Therefore for survival purposes it is perfectly feasible that dogs which return to the wild live a solitary life. An example of how human behaviour affects the lives of wild carnivores which immediately comes to my mind is the example of foxes. Many people assume that foxes are nocturnal animals when they are actually in fact very much diurnal. The reason a lot of people assume that foxes are nocturnal is because they only see them at night. And yet the reason for that is actually because foxes tend to try to avoid humans when they live in close proximity to them. In areas where fixes live far from humans they live very diurnal lives. Examples of this can also be seen in towns, eg foxes will often sunbathe, play, and generally socialise, in the middle of the day by railway embankments, they are able to do this because they generally feel secure from inference by humans in such places. Humans can have a profound affect on the behaviour of wild animals. Having said all that, solitary wolves are far from unknown, hence the common reference to the "lone wolf" by the indigenous people's of the Americas. Therefore the solitary v pack argument is never that clear-cut and straightforward, but there is no doubt at all that wolves/dogs have highly complex social lives, and they are also highly social animals .... imho.
As far as scientific evidence is concerned, it is hardly surprising if you manage to dig up an opposing scientific argument. There are plenty of opposing scientific POVs for most things. Here is one on the widely accepted theory of evolution :
After more than a decade of effort the Discovery Institute proudly announced in 2007 that it had got some 700 doctoral-level scientists and engineers to sign "A Scientific Dissent from Darwinism."
I am not however going to reject the Darwinism theory of evolution because of it, any more than I am going to accept that dogs are not highly sociable animals because some scientist in America or wherever, says so. If you have to regularly leave a dog the best part of the day on its own, then my and most people's opinion is, don't bother getting one.