The inability to attribute a phone call via Salesforce is a bit alarming as this is a huge miss on RingCentral's part. One of the primary reasons to have multiple phone numbers beyond the obvious of going to different people is to attribute where a user found you and called in from. The current Salesforce integration (July 2022) doesn't surface the number that was dialed and therefore lacks the capability to setup dashboards capable of attributing calls from various locations and ability to view the data alongside other Salesforce data.
This data exists within the RingCentral portal reports but is missing in the Salesforce integration. Please add this option to improve reporting where users need it!