How long have they been in the fridge? Are they in damp paper towel?

I have no personal experience with rugosa seeds but I do my seeds in the damp towels and after they've been in the fridge for about 4 weeks I start checking them. That's the earliest I've ever had any germinate. The peak time is usually between 6 and 8 weeks in the fridge. And they will germinate in the towels in the fridge. Once you see the little root popping out of the seed coat you can plant them in a seed starter tray in seed starter soil, not potting soil, with the root down in the soil and the seed head up. Keep the lid on the starter tray to keep the humidity up around them. Drying out is the kiss of death. Put them under lights if they can't go outside in the sun yet. If they're indoors you want the lid of the tray to nearly touch the light source. If they are too far away they'll get long and spindly. Once they get too tall to stay in the tray with the lid on and they have at least one set of true leaves, you can plant them up into cups with holes in the bottom or VERY small pots. Then gradually condition them to the outdoors as soon as possible. As soon as my night time temps are consistently above freezing I harden them off and they go outside in full sun for the rest of the season.

There are many other ways of doing seeds too though. Some people take them out of the fridge after a while and just plant the seeds themselves into the seed starter trays and wait for them to germinate in there. Others just plant them right out into the ground. If you want more information about other methods do a search on here or on google. I'm sure you'll find lots of information!

Seed germination

Seed starter tray

Lid on and close to the light source

Planted up to cups

Seedling nursery outside

This is one of my seedlings from 2006 planted in my garden!