Right, there are retirement/pension investments for Dutch/EU nationals which she is not eligible for because of her status as a US person (in the eyes of the SEC).

So, long story short, she's ineligible for investing as a US national unless she jumps through hoops to maintain a US address and appears to reside in the US. Meanwhile, she's ineligible for investing as a Dutch national because EU brokers won't deal with US nationals. Limbo.