Mike Casey said the company owes him $100,000 after he called the tip line and told them he employed the husband of the woman who tried to defraud Wendy's, and gave them details about the plot, the Contra Costa Times reports.
Anna Ayala and Jaime Plascencia plead guilty last week to fraud conspiracy.
In March Ayala claimed she found a fingertip in her Wendy's chili.
The company started doing its own investigation and set up a tip line and offered a reward to whoever could tell them who the finger belonged to.
Police say one of Jaime's co-workers had lost his finger in a work accident and sold it to the couple.
Wendy's spokesman Denny Lynch said lawyers are sorting through the tip line calls to verify the exact person who deserves the reward.
Casey is adamant the reward should be his wants the company to move faster.