There is no uncertainty about the origin of Aspirin whatosever.

A young chemist named Felix Hoffman synthesized it in 1897. The name aspirin was settled upon in January 1899, between the two finalists euspirin and aspirin.

All use of salycilates in natural form until then was quackery and not the origin of the thing called Aspirin.

Salycilates that are not ASA are not aspirin.