coffee shop

Question

The kashrut organization in my city gave a hechsher to ONE coffee shop which is part of a large chain. the other coffee shops do not have a hechsher, so one cannot eat there. I noticed that the french vanilla coffee sold at the kosher shop was made in the exact same machine that is made at every other shop [i go to the other shops just to get a coffee], which made me wonder whether all the french vanilla coffees are the same. It did not make sense to me that the head company would alter its recipe for one simply store. So I emailed and called the head office and this was their response: quote: "Dear Barry, Please rest assured that all of the French Vanilla Cappuccino that you enjoy is the same in all of our stores. We have one supplier for all." That was a good sign. Then I asked if the same utensil is always used to hold the french vanilla coffee and nothing else. I was told that the machine that makes the french vanilla coffee has four compartments that maked 3-4 drinks, and each container can be used for every drink. Furthermore they are cleaned with water and a sponge. So my question is the following: If I find out that the rest of the drinks made in this machine are kosher (which they likely are b/c these drinks are also sold in the machine at the kosher coffee shop), is it ok to drink the french vanilla at a different coffee shop?? what about the cleaning process, this is what I am most concerned about. Let's say the same sponge that cleans the coffee containers also cleans the bin that held the ham or something. Do I need to be concerned about this?