It is true that the article doesn't expound upon the order of agriculture and sociocultural change, but there is somewhat of an implication. You'll recall from the article that construction of the site is first dated to ca. 11,000 years ago -evidence for domestication is found at around 10,500 in the region.
Of course this doesn't show that the workers started construction then got hungry 500 years later, but it is telling that widespread agriculture (cultivation of plants, domestication of animals) is evident after construction and not before.
There are many, many indicators of agriculture, which include teeth of ovicaprids, bovids, and swine (sheep/goats, cattle, pigs) and microliths that have a special type of wear called sickle gloss. There are many other indicators as well -but non show up prior to the megalithic construction.
The implication, therefore, is that there was a motivation to create the site that was other than agriculture since agriculture followed. The man-hours and caloric intake required to do the work demands more than a foraging lifeway. Foraging (a.k.a. hunting/gathering) takes time and work by itself and foragers can't generate that sort of calorie requirement. A more efficient strategy of food production is the natural progression from foraging to cultivating and domesticating -one gathers plants and animals then controls where they grow and live and the rate at which these resources are used.