Do these matches have the same contact person?
Yes.
Those are likely links of an uncle or aunt to a niece or nephew, or a grandparent to a grandchild, half siblings, or double first cousins.
The top looked progenitor/offspring to me. Followed by half sibling. Followed by half nieces/nephews. That was what I was thinking of the results.
When I transferred from the usual Gedmatch to Genesis, It brought up about a dozen bizarre matches which were an error.
You could identify them because, although they showed on the one-to-many list, some very high up my table ( 9 in the top 70), if you went further, and did a 1-to-1 match comparison, it told you you had 0 cM of common DNA. I had to email gedmatch, and they resolved the problem!!
In the attachments of my 2nd post are a couple of the 1-to-1 comparisons. They're consistent with the one-to-many match results; very high in cM count.
I'm still somewhat expecting (hoping?) it to be an error of some kind.