Is it permissible for a contracting company to pay a commission to engineers in engineering consulting offices in exchange for bringing in projects, whether this is with or without the knowledge of the office owner?

It is permissible to allocate a financial reward to whomever brings a project to your company, whether they are from the general public or consulting firms. However, paying these amounts to engineers working in consulting firms without the knowledge of the firm owners is impermissible, as it aids them in betraying their employer.