What is the ruling on working for a company that delays in fulfilling its obligations and sells smuggled goods, knowing that these goods cause no harm other than entering the country without official permission?

If your work in the company is in a permissible field, there is no objection to it, even if the company engages in impermissible acts such as delaying the fulfillment of rights or selling smuggled goods. You should advise its owners to avoid prohibitions.