I'd like to point out that <uij> isn't a part of standard Dutch orthography, it represents a diphthong that is normally written <ui>. The diphthong (i.e. /œy̯/ in northern Dutch dialects the first vowel of the diphthong is pronounced less rounded so it's realized something like [ʌ̈y̯]) is pretty unique to Dutch.
French and other Germanic languages except English have similar types of vowels (i.e. front rounded vowels), but generally they're quite uncommon so it's not surprising that people with English as a native language, find it difficult to pronounce. If you speak French, you might be able to pronounce <ui> (or <uij> in this case) by saying the French <oe> and the French <u> after each other like a diphthong.
Anyway, for those who know IPA <Kruijswijk> should be pronounced /'krœy̯s.ʋɛi̯k/ (although if you hear a commentator from the Netherlands saying it, there's a good chance it'll be more like ['krʌ̈y̯s.ʋæi̯k] which is how I pronounce it as well) and I'm not surprised at all that people who don't speak French or non-English Germanic languages have a hard time pronouncing that.