I actually just worked on this with our ops team.
V1 - everyone fills out our program form, then they go into an Marketo sequence that sends them the link to join the community. One of the emails is to book a call with me, I had at least two people not customers book calls (which I canceled). So not ideal.
V2 - (only gets into sequence if matched or field is manually checked in Salesforce) - once they fill out form, system waits 10 min to match them up to Salesforce, if that doesn't work it tries again 24 hours, if that doesn't work every Tuesday we get a report of folks that didn’t match up (usually only 1 per week needs to be manually added)