The Bills signed Johnson to a one-year deal.
While James Franklin said his wideouts have improved during spring practice, the Nittany Lions are experiencing the same struggles they had a year ago.
"We try to keep things simple so we can play fast."
Allen's development as a running back has changed under new offensive coordinator Andy Kotelnicki.
The Nittany Lions are also set to face Nevada and Villanova in the same season.
Scott previously won a Super Bowl with the Los Angeles Rams.