Made sushi for poker party; what’s best way to store at safe temp for open grazing at a party?

I have this oval-ish plastic dome I put over the top of 2 pans, and in middle of 2 pans were 2 frozen solid thin but large rigid ice packs. I kept infared temp testing even an hour and then 2 after serving and the rolls were holding at between 40-45 degrees fahrenheit, which is the very bottom of the danger zone.
I didn't use any real "raw fish". Just smoked salmon, imitation crab meat, and basically cooked cocktail shrimp.
I ordered a slightly more sophisticated sushi cold serving station that arrived the day before my party but unfortunately they sent the wrong item and it wouldn't work.