Issue
You would like to use the 'SFDC Oppty Campaign ID' as a constraint for the Smart List filters ' Has Opportunity' and 'Opportunity was Updated', however, it does not appear as an option.
Solution
By system design, there are some opportunity fields such as 'SFDC Oppty Campaign ID' that are restricted and cannot be made visible in Marketo as a constraint or filter.
One workaround is to create a custom field in Salesforce on the Opportunity object that holds the same value as the 'SFDC Optty Campaign ID' field. As a result, this field will appear in Field Management and become visible as a smart list constraint or filter in Marketo. If you would like to implement this, reach out to your SFDC admin.
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