If I may chip in to the argument about disobeying orders. I haven't had a chance to watch the program yet so apologies if this has already been covered.
One of the PQ17 escorting destroyers was Keppel commanded by Jack Broome.
I need to dig out his book but IIRC he did question the order to withdraw initially (ack flag at the dip) but had confirmation and when alongside the Admirals cruiser in a high speed chase to the south, which he assumed was to engage the Tirpitz, asked why they had withdrawn when discovering it wasn't to engage the enemy. But by then it was too late to go back and had to abandon the convoy
It is possible that he may have ignored the order to withdraw if he was in full possession of the facts?
He went on to say he felt thoroughly ashamed and felt the navy had let down the merchant marine badly.