I know this may sound simple, and I feel like I know what I should do but I need backup!

Our customer, construction business, writes large check to subcontractor. Check is payable to subcontractor's business. Sub is not customer and not from our community. Check is approved to be cashed (I know, I know.... my old teller supervisor days haunt me still) and cash is given to subcontractor. Teller coompletes CTR however she does not have EIN for subcontractor's business (nor do we really know anything about ownership of business....) Can we complete CTR in name of subcontractor with the business as DBA (business is not in secretary of state's database) or do we need to obtain the EIN and business information from the subcontractor. Anyone have a situation like this they could advise me from?

If the check is payable to the business, unless the business has signed the check over to an individual, you are going to have to assume that the benefit is going to the business and the individual cashing the check is the transactor.

How you are sure that the person standing in front of you can negotiate the check on behalf of the business - as you alluded too - is a whole other story.