All US brands of the injectable B12 contain aluminum.
I saw that the sublingual pills had benzyl alcohol and I avoid all organic solvents especially any with a benzene ring. It is used to stableize the cobalamin and I think that's the purpose of the aluminum lake in the injectable. When a person has severe maladsorption they may need to take injections despite the negative side effects. I think that an injectable B12 could be made with pure B12 but it would have to be freshly made and most Drs or pahrmicists are not trained to prepare this and the insurance Co.s might not pay for the added expense.