There are certain instances in life you have to decide on your own if you’re comfortable with such a situation (the Fifth Chelek of shulchan oruch). The Coffee is kosher don’t let anyone tell you otherwise but the least of the issue are of it being washed with products that might have been touched by treif in addition to Maaris Ayain of going into a non-kosher restaurant. Ask your rabbi if he thinks it ok than if your comfortable with this enjoy the coffee and try not to care what others might think.
