http://www.yolysbistro.com/index.php I don't know if you saw some news article, but it appears to be open judging from their website, it is also possible that it might be closed for winter... I don't know what you found in your web search.
here's the link for Yoly's address. I don't know why it isn't giving a place marker link.
I can't offer any expertise for Fairbanks or Denali, but seeing as I live in Anchorage and often had layovers in Seward as a tour guide on the Alaska Railroad, I can offer a few opinions in those two cities.
In Anchorage --as you have heard multiple times on this list already, Moose's Tooth and Bear's Tooth are both excellent, but also popular hotspots for locals. You can't make a reservation (except with very large groups?) at either, so it is best to expect a wait, possibly a fairly significant one, at dinnertime. I haven't ever had to wait more than about five or ten minutes at lunch. Nonetheless, you can grab some of their well known beer (or excellent rootbeer for the kids) and hang out in the beautiful Alaska summertime weather. Neither restaurant is directly downtown, so that is certainly something to keep in mind.
I do personally really love Simon's, though I have heard slightly mixed or blah reviews of the food, I have had overall good experiences, and it might be worth it just for the view. Ask for a table near the windows.
Additionally Glacier Brewhouse always seems to be a hit, a variety of well done dishes, nothing particularly revolutionary, but all very enjoyable.
On the topic of Seward, since you seem to have gotten mostly warnings and few recommendations at this point, I will try to contribute. I really enjoyed Yoly's Bistro during my time, its on 4th avenue. Eclectic menu, but all delicious and very fresh.
Sweet Darlings is a can't miss. Practically across the street from Yoly's, it is a candy shop with delicious handmade candy and lovely gelato. Alaskans are an ice cream loving bunch, and Sweet Darlings is a lovely way to satisfy the craving.
Apollo's is a place to get decent pizza and greek food. Not an inspiring choice, but not bad either. The Sea Bean is a nice coffee shop, great if its raining outside and you need a respite, they have a bookshelf full of travel books and a strange other assortment as well as board games to play if it is pouring. The Sea Life center is a good aquarium/research center. Go enjoy the interesting exhibits, ask about the research.
At some point during your trip you should definitely make sure to get halibut fish and chips. Because ultimately, halibut makes really great fish and chips.