When I was a young boy my dad took me ice fishing. We would catch a bunch of yellow perch and toss them on the ice where they would freeze solid.
When we headed home we picked them up and put them in a 5 gallon bucket. After an hour drive home we got the bucket out of the back of the truck and dumped them on the basement floor by the drain to �soften up for cleaning�.
After getting out of our sub-zero clothes and having something to eat we headed downstairs for fish cleaning.
I would put a couple of those perch in the 5 gallon bucket with some water and they would un-thaw and start swimming around.
Does this answer the question?
No.

My post was directed at short term to long term effects vs. if they would just survive the experience. You would not see life threatening fungus on fish right away after ice fishing.