A few points:
Soap is pogame taam, and as such if it is used at the beginning of the washing process, it should be mater any issue that would otherwise arise.
Second of all, is that water coming out of a urn is coming from a kli rishon, and as there is no heating element in the kettle (maybe a dishwasher is different), the worst that the pot would be is a kli sheni (think simple hilchos shabbos). Now water in the pot emits steam, but a kli sheni itself, I believe, isn't nosane taam, so when the steam goes into the spout, what's the issue?