How does the SFDC connector determine the winner or loser for the Salesforce ID?
"message": winner :0038L00000CQWpdQAH, losers: [\"0038L00000CQWypQAH\"]"
It does a lexicographical comparison for crosswalk and sends the lower value as the winner, which means that the record created earlier in Salesforce will be the winner in Salesforce. And it can be a different entity from the one winning in the tenant. This behavior can be changed by using a custom merge service.