"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 think there's a meaningful distinction between workers who earn their wages in the formal economy and workers who earn their wages in the informal economy. It sure is more substantial than the so-called PMCTM, where the original authors lumped teachers, accountants, and nurses together with middle managers.
Lumpenbourgeoisie are definitely a thing. What else would you call a mob boss or a drug lord? They aren't really bourgeois because they lack legal legitimacy. If nothing else, the lumpenbourgeoisie is a strata of the bourgeoisie that the bourgeois state is at least nominally opposed to.