An affiliate link can return HTTP 200 and still fail commercially. Link Health examines the complete chain.
Evidence layers
- Published link versus intended link
- Redirect chain and tracking-domain hop
- Publisher ID or Sub-ID survival
- Wrong product, homepage or cross-domain drift
- Geo and device context
- Availability
- Transaction-level attribution evidence
A visible tracking parameter is not enough to prove commission attribution. A single observation is normally a candidate issue until repeated or supported by stronger causal evidence.