If they think you are a fraudster or terrorist (etc) they have to refuse giving you an account and must silently report you. What would happen if they skip/delay the reporting part?
>What would happen if they skip/delay the reporting part?
They wouldn't. Typically banks take the approach of filing as many reports as they can. If you're overeager in filing the reports, nobody will look at them and you will not be blamed for not filing those reports.
Google for something along the lines of "suspicious activity report flooded" and you'll find endless stories demonstrating how ineffective these systems are.