The linebacker agreed to take a pay cut to stay with the Broncos, but a fax blunder by his agent resulted in the team releasing him.
Miller, who was the Broncos' sacks leader in 2012, told NFL Network: "He was our leader in the locker room. He was our rock.
"He showed me how to be a technician on the field. He showed me so much stuff on the field, how to be a professional, how to conduct yourself off the field. He's truly going to be missed.
"Before anything, me and Elvis, we're brothers. I wanted what's best for him and going to the Baltimore Ravens was a better fit for him."
Dumervil has been with the Broncos for seven seasons prior to his release.