If 2nd Date/Time Row, Remove Both

FYI Anonymous - neither solution above will work if you have the same memid check in on a different day. The below will handle it if it does. This speifically checks for the 52 and 192 codes as well, so code 171 would not cause this to get deleted for example.

But if you have multiple checkins a day, this will not work either, or a checkin at 11:50pm and a checkout at 12:03am the next day. We'd need to see a more comprehensive data set to see how to account for other possibilities, including additional columns if necessary.

1) In Power Query, select New Source, then Blank Query
2) On the Home ribbon, select "Advanced Editor" button
3) Remove everything you see, then paste the M code I've given you in that box.
4) Press Done

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("dZBLCsMwDAWvErwORF9L8h0K3Yfc/xqRU7qp1ZXgMYOkd55NhR3N2t7CgTmnHoQHAcFGA21IbO/XjKld+5f3DJDBmFZBeyHEI4hD/xV8QCE4ZGDdQlcepeBxLgAGLYScqzAvD+sCBV8dNKvB/LkvL/tgLQT506lEtvThMVK4bg==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [chkinid = _t, memid = _t, checkin = _t, stationid = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"chkinid", Int64.Type}, {"memid", Int64.Type}, {"checkin", type datetime}, {"stationid", Int64.Type}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Date Only", each DateTime.Date([checkin]), type date),
    #"Grouped Rows" = Table.Group(#"Added Custom", {"memid", "Date Only"}, {{"All Rows", each _, type table [chkinid=number, memid=number, checkin=datetime, stationid=number, Date Only=date]}}),
    #"Added Custom1" = Table.AddColumn(#"Grouped Rows", "Remove", each List.ContainsAll([All Rows][stationid],{52,192})),
    #"Filtered Rows" = Table.SelectRows(#"Added Custom1", each ([Remove] = false)),
    #"Expanded All Rows" = Table.ExpandTableColumn(#"Filtered Rows", "All Rows", {"chkinid", "checkin", "stationid"}, {"chkinid", "checkin", "stationid"}),
    #"Removed Other Columns" = Table.SelectColumns(#"Expanded All Rows",{"memid", "chkinid", "checkin", "stationid"})
in
    #"Removed Other Columns"

AlB and edhans 

Thanks for this... some weirdness, though (and both methods got the exact same results):

1. It's not removing all people who have scanned at check-out stationid 192 (see memid 76795).  It did remove memid 98033 who checked out.
2. The checkin date from the query doesn't match when they actually scanned in.
3. The stationid from the query doesn't match the stationid that they actually scanned in on.
4. It's also not picking up any scans from memid 104958.

In the below data, I've included checkin and stationid from both the query and the table for comparision.  The table names are in all caps in each column heading.  

Also - I apologize for not mentioning this earlier, but stationid 56 is a secondary check in station within the facility and should not be counted as a check out when it occurs after initially scanning at stationid 52 upon entry.  Stationid 187 is an alternate initial entry to the building and should be treated the same as stationid 52.