I do not recall that authorities have made any kind of statement to indicate whether or not any remains were found during their recent digging. In fact, no mention of any kind was made regarding anything that they might have found.
From the photos I saw, there were actually several dig sites, all located in a row, and all seemed to be getting an equal amount of attention, judging by the piles of sifted dirt in front of each.
Having been on similar archaeological digs, I can say that even if no bodies were found, the digging, sifting, and careful cataloging of any finds can be of much use to investigators. For instance, finding trash or items which date to a specific time can possibly pinpoint or possibly eliminate an area for future digging.
If in one spot archaeologists were to find undisturbed 16th century pottery, it would be unlikely that a body was buried there in the 20th century.
The ground, itself can indicate whether or not it had been dug into in the recent past, based on disturbance patterns or mixing of clay with topsoil. Contaminants in the soil might indicate chemicals used to dispose of bodies. Lime deposits might also indicate an attempt to cover a grave.
Identification by DNA matching is a very recent thing. Twenty Five years ago, I recall a case where bodies were located and identifications were made using World War II era dental records, missing aircraft reports, and general descriptions of the men.
DNA matching does not require that a body be reconstructed. It does, however, require that a good sample be obtained which will yield enough matching points to a master sample known to have been from the victim or from a close maternal relative. After a body has been decomposing or exposed to the elements for a long time, DNA is degraded, so finding a good sample may take some time.
A good DNA sample might not come from just a body or body part. It could be found on other evidence as well, such as a piece of clothing or a weapon found during a search.
As to how much time it would take - that would depend on a lot of different factors. Even a controlled comparison of perfect samples could take a few weeks.
Then there is the question of how investigators or prosecutors choose to use any evidence found. Do they charge someone with a crime, or do they continue to look for more evidence to support their case? It is unlikely that results of any DNA matching would be released prior to further searching.
