@Felipe-CS Are you currently leveraging lifecycle stages in your portal? In addition, you could also leverage association labels to notate who the primary point of contact is on the deal. That would give you the ability to pull a specific associated contact to the deal.
If your lifecycle stages are tied to your deal stages then you could pull the data like that. For example, when the deal reaches Demo Scheduled stage in the pipeline, the associated contact’s lifecycle stage gets updated to Opportunity.