Referrals are always dicey. Alot of spider will pull your redirect but not follow it. - spiders will follow the link to your redirect which is on your site, but not follow the redirect itself off the site.
- browsers. many browsers can turn of referrals.
- filtering agents can block referring strings (adult filters, banner busters).
- firewalls, gateways, and various proxy servers can all block referrals.
Best way when disputes come up like like your situation, is to compare IP addresses. Take your tracking list and what lines up with an ip at that time in their stats. If they click on your redirect, and within a few seconds show up in the log on the destination site, that's your click.
