Analytics defects are product defects when teams use the resulting data to allocate time and budget. Validation belongs in the release process.
Test expected events, prohibited duplicates, property formats, identity transitions, and consent states. Use a small set of canonical journeys and record evidence for each check.
Assign one owner to accept the instrumentation, while keeping implementation responsibility with engineering. If a release changes a critical journey, repeat the relevant checks instead of assuming old coverage still applies.