Editing Wikipedia for pay without disclosing it violates the site’s Terms of Use. It is also, in practice, a poor bet: what is hidden is usually found, and what is found is usually reversed.
Volunteers track editing patterns closely. An account that only ever improves one company, or a burst of new accounts around a single page, invites scrutiny, and scrutiny of a paid, undisclosed edit tends to end badly for the subject.
Disclosure is not a weakness. Declared on the record, it lets reviewers judge the edit on its sourcing rather than its provenance. We operate every account openly, with the firm and the client named.
The short path is a trap. The durable entry is the one that could survive its own history being read aloud.