What is the correct entry point for capturing coverage data

This is not how coverage should be tested, or probably not even what it means. coverage “testing” is part of having a testing plan and the coverage information lets you know how good your testing plan is (for some definition of good, as rarely a 100% coverage is worth achieving in a complex code).

What you are doing is more of a profiling, which is a worthy information by itself, but it is not actually related to coverage.