I think that a judge would have appointed the processioners.  Does anyone know if there would be any kind of record of the processioning?  

          If filed properly, the documents were put in drawers labeled "Processionings" in the probate court, alphabetically under the applicant's name.  A verbatim copy of the documents was recorded in the Ordinary's Minute Book or the Probate Court Minute Book, depending on what time period the processioning was conducted.  The complete set of documents, including the plat, were supposed to be copied into the minute book.  Depending on the competence or carelessness of the ordinary or probate judge, this record may or may not be complete.  On the other hand, documents in the original file sometimes get lost, or the original file cannot be found at all.  It is best to check both sources.

          Records are recorded in the minute books as they are generated, so that they are pretty much in chronological order.  Since you know the date of this processioning, go to the probate court, pull the minute book for that time period, and turn to the pages that contain the date that you have.  You may have to flip back and forth a little to find the record needed.  Once that is found, you will have the name of the applicant, and that can lead you to the original file.  The minute books are usually indexed in the front or back.  If you already know the name of the applicant, you can check the index in the relevant volume under that name and it should lead you directly to the record.

          The competence of probate judges, like public officials in general, varies greatly.  Office holders often know little about what their predecessors did and are often unaware of how their predecessors filed things.  If the present probate judge cannot direct you to a drawer labeled "Processionings" that does not necessarily mean it is not there--you will have to look for it.  And sometimes the labels on the drawers are missing, which means you will have to look in each drawer until you find the processioning files.

          I have been directly involved with three processionings in my lifetime.  In each case they greatly compounded and added to whatever problem there was about the boundary.  The county surveyor, who presided, was usually the least competent surveyor around.  In two of the situations, he was not even licensed.  The processioners were laypersons who knew nothing about surveying, boundaries, or land titles.  The processioning law was thankfully done away with in 2014.