#52Ancestors: Week 17 - DNA: A Jigsaw Puzzle

I sent my DNA to Ancestry 5 or 6 years ago.  I did it more for the ethnicity estimates than anything else.  After the most recent update, my ethnicity looks more or less as I would expect:

46% Southern Italy

29% Sweden and Denmark

22% Norway

Various smatterings from a few nearby places.

Eventually, I started labeling my DNA matches by family surname using Ancestry's colored dot system.  No surprises as I combed through the 1st-3rd cousins.  When I got to the 4th-6th cousins, though, I came across people I could not easily attach to any family line...and yet they all connected to each other.  A DNA newbie, I didn't know what it meant to share 45 cM (the highest number of cM shared in what I labeled "Total Mystery matches), so I clicked the link:

Sadly, this did not help much in the way of clarification. 😂  However, as I clicked on Shared Matches for one of my "Total Mystery" people, I was surprised to see two identified DNA matches - 2 great grandsons of Cora Pearson, my great grandfather's sister!  

Sorry to disappoint, but this is not the part where I tell you how all the "Total Mystery" people are related...  You see, it's complicated (like a relationship on Facebook).  Cora Pearson married Bailey Arter, and Cora's great grandmother on her mother's side was also an Arter.  So maybe these mystery matches are descended from a Pearson...or maybe they're descended from an Arter - quite possibly both.

I have spent several days fleshing out peripheral Arter family members, but to no avail.  The surnames I seek (those frequently repeated in my "Total Mystery" matches) are nowhere to be found.  Now, at this point, someone usually inquires, "Why do you care?!  They are distant cousins, at best!" (It's usually my dad.  Dad, if you've happened to click this link, please read on to find out why I continue.) I don't know that I necessarily have an answer other than, I treat genealogy like a jigsaw puzzle.  These "Total Mystery" matches don't fit snugly into my puzzle framework, and I want to know why.  Is there a missing piece in the box or maybe on the floor?  Have I accidentally connected two pieces that don't belong together? I am continually inspecting them, rotating them, rearranging them, trying to determine where they fit, and waiting for that a-ha moment when I can complete the puzzle.

Suggestions for how to go about completing this puzzle are most welcome.