I was wondering why that admiral so willingly showed the video to congress. [View all]

It obviously shows a murder in full detail. One that someone is ultimately responsible for.

Then I thought back to Hegseth saying kill them all. He seemed quite proud of the decision.
Then he learned that it was a very real war crime, one that will be over his head for life. He would not be able to leave the country lest he may be arrested.

So all of a sudden he changed it to claim the admiral in charge made the decision to kill them but he supported him fully.

When asked why he was watching the attack in real time and, as the commanding officer, didn't stop the 2nd strike, he said he didn't see the two survivors. That throws it back to the admiral again. Hegseth was told to produce the video and he stalled then refused.

Now Admiral Scapegoat himself brings it in for Congress to decide for themselves if Hegseth would have missed seeing those two survivors.
By all accounts he could not have missed it so the responsibility goes back up to Secretary Talk Show.

I think the best metaphor here is someone caught a hot potato.