I could give you a talking to about our exaggerated modern perception of 'risk', but it would be quite boring for both of us.
a cropper one day, but to be honest, a few days in bed with food poisoning sounds like a bit of a luxury nowadays.
fish is actually one of the only proteins you can refreeze. You get a bit of fibre degredation and fat migration (on the oilier types)but it will be ok.
It will stink to high heaven well before it is unsafe to eat.