Glossary
Attribution
Deciding which placement, campaign or channel deserves credit for an outcome.
A short link can attribute a click, which is a narrow and honest claim: this placement produced this many opens, from these countries, on these devices. That is the whole of what a redirect can see.
It cannot attribute a sale. The redirect is the last thing the shortener observes, and what happened on the destination page belongs to the destination. Joining the two requires something running there, tying the visit to the eventual purchase.
Any tool claiming otherwise from the link alone is either running a script on your site or describing something it does not do.
