Was the shipment they wanted going to or from the US? If so, you could check to see if they are a registered carrier using the Safer, company snapshot function. Also, ask then to send you their vehicle insurance policy and follow up with their broker to see if it is legit. No doubt a serious scammer can skirt these checks, however the information usually can give you an idea about their operation.
Two Roads Logistics is a broker that is very clear on the website, also we do not contact brokers for freight, we only contact carriers to offer business. All our clients are shippers or wholesalers only. Should you have any concerns please contact message me directly. Thank you.