I never heard of 88, but the ok symbol was definitely a 4chan creation:

https://en.m.wikipedia.org/wiki/OK_gesture

So, I’m very skeptical of “secret Nazi dog whistle” nonsense.

If something is incorrect, it sufficient to say that it’s incorrect, and explain why. Claiming something is a secret dog whistle for Nazis just means that you don’t have any credible refutation about its correctness.