The problem for compliance research is, that when it comes to terrorist financing issues, not only are the details of ongoing criminal investigations unavailable to you, but even the identities of associates, counter-parties, financial institutions where they have operated, names of their front businesses, and even names of close relatives, are all classified, and the information restricted. Those investigations, which can drag on literally for years, can impact your bank, because you have no knowledge that an active organisation that is funneling money back to the Middle East or Asia, using local financial resources, including yours.
Of course, any enhanced due diligence that you perform on a prospective customer whose company is engaged in volume business with countries located on the Middle East should, frankly, be the subject of enhanced due diligence in advance of account opening, due to terrorist financing issues, especially those who trade with entities in Lebanon, Iraq and the UAE. That's just prudent risk management.
Whichever solution you choose, remember that whilst you should be guided by risk management and cost management considerations, if you are not comfortable with the quality of the results, make your concerns known to your decision-makers to decline the client. You do not want to accept a new client who could be sending funds to designated terrorist organisations.