مچھلی اور دمِ مسفوح
Jzk for that. After listening to the videos the original argument of presence of blood in fish still remains the same that All fish, whether whale or trout, tuna or salmon, have blood and tazkiya is not applied to/required for them.
The primary requirement is of tazkiya of flowing blood (damma-masfoohan). Therefore, if a fish contains that kind of flowing blood the way we see in cattle, then of course the requirement will apply as directed. In cases, usually the small fish that we eat, there is no such flowing blood, therefore the requirement of that kind of tazkiya does not apply.