When adding the step in the flow 'Member of SFDC Campaign' can it sync and bring it records that do not exist in Marketo (therefore create a new record in Marketo)?
Hi Amanda! If you have SFDC synced with Marketo, any record added in SFDC should automatically be added to Marketo, as well. In which case, any SFDC members added to a campaign will be pulled into that Smart List. Depending on how many records are new, the sync could take a few minutes, but I've never had a problem with this.
Just to be clear:
adding a Lead in Marketo to a campaign or flow action will only affect Leads that qualify for the Campaign. Adding to SFDC Campaign will not inherently sync a lead that is only in SFDC and a member of that SFDC Campaign. If you want to do so, you can sync the Program to the SFDC Campaign and it should bring in ALL members of the SFDC Campaign regardless of origin.
+1 on Jennifer too.