"Lumpenproletariat" is exactly the kind of idea an educated German theorist would come up with in the wreckage of the industrial revolution and it's ridiculous to try to carry that notion forward to the age of cell phones and heavily armed maoist prostitutes and if anyone can't understand that you should throw grass at them until they stop being dorks because they're too far gone to touch it themselves.
Like ffs read even one anthro text about black market and grey market economies and stop treating The Man's legal system like anything but a criminal organization.
I have no idea where you're getting this from. Saying someone is a Lumpenprole isn't a moral judgement, just an economic one. Someone who grows rice and the bandits that steal it have different relations to the means of production. They are not just proles who break the law.
Engels was largely revolutionary but he was also bourgeoisie, that does not mean that the bourgeoisie as a class are revolutionary. Also, many ML theorists argue that Lumpenproles do have revolutionary potential while not denying they exist as a class.