What is the difference between syncing a lead to SFDC and Adding a lead to SFDC?
There is no "Add to SFDC" flow step, but there is an "Add to SFDC Campaign" flow step - is that what you are referring to? "Sync Lead to SFDC" only syncs the lead, where "Add to SFDC Campaign" syncs the lead and adds them to a specific SFDC Campaign.
Either way, the lead is sent to SFDC, OR updated in SFDC.
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