Merging column

Nagababu 
According to your condition Jane doe should be 104.. rohit1991 and BIswajit_Das  are correct..
I have also checked in Power query also and below is the code

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlTSUTI0AJFe+Rl5QMolP1UpVgcmYYRLwhhIBhdkgiTSU/OL0pHlTECaEvNSMTSZAknfxKJKDAkzhDXBuZklGUhS5rhcYIEpYQSWsERYjzAM5F5DQwM0PbEA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [customer_employee_id = _t, theatro_employee_id = _t, first_name = _t, last_name = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"customer_employee_id", Int64.Type}, {"theatro_employee_id", Int64.Type}, {"first_name", type text}, {"last_name", type text}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"first_name", "last_name", "customer_employee_id"}, {{"Count", each _, type table [customer_employee_id=nullable number, theatro_employee_id=nullable number, first_name=nullable text, last_name=nullable text]}}),
#"Added Custom" = Table.AddColumn(#"Grouped Rows", "Custom", each let
            innerTable = [Count],
            rowCount = Table.RowCount(innerTable)
         in
            Table.AddColumn(innerTable, "check", each rowCount)),
    #"Removed Other Columns" = Table.SelectColumns(#"Added Custom",{"Custom"}),
    #"Expanded Custom" = Table.ExpandTableColumn(#"Removed Other Columns", "Custom", {"customer_employee_id", "theatro_employee_id", "first_name", "last_name", "check"}, {"customer_employee_id", "theatro_employee_id", "first_name", "last_name", "check"}),
    #"Added Custom1" = Table.AddColumn(#"Expanded Custom", "MergeFlag", each if [check] > 1 then [customer_employee_id] else [theatro_employee_id]),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom1",{"check"}),
    #"Sorted Rows" = Table.Sort(#"Removed Columns",{{"theatro_employee_id", Order.Ascending}})
in
    #"Sorted Rows"

the same logic i have applied in DAX as well

MergeFlag = 
VAR _tag =CALCULATE(
    COUNT('Table'[customer_employee_id] ),
    ALLEXCEPT( 'Table','Table'[first_name],'Table'[last_name], 'Table'[customer_employee_id] )
)
VAR _MergeFlag = 
IF(
    _tag >1,[customer_employee_id],[theatro_employee_id]
)
RETURN
_MergeFlag

Below is the pbix file.

Regards

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