Brown leaves after becoming a defensive analyst for the Nittany Lions last season.
Campbell totaled 90 tackles, 7.5 sacks, an interception, and a forced fumble across two seasons with the Tar Heels.
Lamah is the second linebacker to commit to Penn State in the class of 2026.
Wiggins had offers from Cincinnati, Syracuse, and Kentucky.
Meyer became the fourth Nittany Lion to find a new program this spring.
A variety of draft experts expect Penn State to make a splash in the first round once again.