Parker was one of the biggest scumbags that have ever walked the earth. However, Elvis discovering speed in Germany didn’t help!
Speaking with docents at Graceland and Tupelo was interesting. Vernon Presley was blamed for not stepping in to stop Parker’s aggressive management/booking activities. The story went along the lines that Elvis was not able to deal with his addictions etc. due to the stress of his career, and no one took a strong stand to help him. Who knows? I think media has occasionally promoted this.