Hi @Dwyte there isn't a direct metric or dashboard report in 3CX that shows the exact match percentage for CRM lookups. The easiest way to calculate your match percentage is within Salesforce and run a tsk report filtered by call source/type.
The other alternative is by checking the pbx logs, go to 3CX admin Console > Dashboard > Activity Log > Settings and set logging to Verbose.
Let it run for a test period (e.g., a few hours or a day) then from dashboard click on support info, download the file and then open the logs folder and search the lookups within the 3cxSystemService.log file.
Remember to turn Verbose logging back to Low once you are done so it doesn't inflate your disk usage.