If one puts cold milk into a steel pitcher which was washed in a dishwasher with treifus, one is allowed to drink the milk since the milk is not stored in the container for 24 hours. Also, there was probably soap in the dishwasher. (We seem to rely on soap, despite that the shach and taz don’t like this heter.)
Now, since the trays were rinsed, and there is no reason to think they are ever used for hot food, then even if the above was not true, the milk in the pitchers would still be muttar.