Apparently, Nederlandsen exists, at least, according to Wiktionary:
(My partner, who is a native speaker, said it's possible it exists... I've just asked another native speaker and fellow mod just in case - I'll get back to you as soon as I can).
Hope this helps.
I'm curious about this as well. I always thought the Dutch "ee" was pronounced more like a long "a" in English, but it is clearly pronounced with a long "e" in English in this example and I've seen posted in other discussions that it is pronounced correctly in these examples. If the examples are correct, then I've been pronouncing these incorrectly the whole time and will need to rework how I speak Dutch.