As real estate agents we are not obligated to be polite and respectful only to our customers but also to our fellow agents. If a customer comes in the office looking for a particular agent or calls with the name of that agent we must direct them to the right person we do not want to be dishonest to our co-worker and think that they are not going to find out. Furthermore the customer will see that you are not been honest.
Different circumstances call for different actions but when the customer is clearly working with a specific person and has not come to you asking for your assistance but instead looking for their realtor please do not get involved specially when is a buyer. Remember that you treat others the way you want to be treated and this is definatelly something you dont want done to you.
Following the rules of ethic could be tough in this economy but stealing is not the way to make ends meet.