No way Lindell goes this year, no matter how well Potter does or poorly he kicks. As stated numerous times, the best predictor of future behavior is past behavior. He's proven to have a decent leg, accurate and grown to understand the winds of the Ralph. He's been reasonably reliable as a clutch performer and I believe the FO sees it, hence the extension.
The tough choice for Buddy is whether to take a roster spot for KO duty or to another position. Frankly, I don't know if Potters' performance is even going to be a deciding factor as one of the other guys shining SO bright that they are forced to redistribute the 1/53 in the others' favor.