It seems like there are lots of Holland America cruises that are listed with incorrect information on CruiseFish. Generally this includes lots of cruises that are NOT sold out showing as sold out and many cruises with prices that do not have an "updated" date since early January. I believe Holland America changed their website recently with how to list available rooms for booking so perhaps this is part of the issue.
As just one example, Maasdam has lots of 7 day cruises listed in Canada/New England for May-August 2017. According to the HAL website none of these is sold out. If you go to the CruiseFish page below though, about half of them show up sold out on the cruise type listing.
If you click on a "sold out" cruise, the cruise price page still shows categories and prices available.
I haven't looked at every HAL cruise of course but looking at a random sample I also don't see any price with an "updated" date later than 1/4 or 1/5 earlier this month. This is independent of whether or not cruises show up as "sold out" on the cruise type listing pages.
Both of these issues make me doubt if CruiseFish would actually pick up any change in price of HAL cruises.