On September 29, 2020, Butler was signed to the
Philadelphia Eagles active roster off the Panthers practice squad and converted to tight end.
[12] He was waived on October 31, 2020,
[13] and re-signed to the practice squad two days later.
[14] He signed a reserve/future contract with the Eagles on January 4, 2021.
[15] He was waived on August 23, 2021.
from wiki
Given what little I heard when he was here, I'm afraid he wasn't trying or able to learn and improve within the scheme the Cardinals wanted. All physical talent maybe?