I was in the Navy for 5 years and worked closely with SEALs in my line of work. A buddy of mine is a SEAL and he has his doubts about the raid. He said it doesn't sound anywhere near the way a SEAL time carries out a mission with a valued target. Not meaning to seem like a conspirator lol but I have trouble trusting everything my government tells me.
I recently RO'd a match with a Delta operator who just retired from service a couple of months ago. We got to talking about the role of special forces in our current war and he said (as expected) that there is a lot going on that no one knows about. Nothing was said about who carried out the OBL raid, but he said that it went well considering the problems that the soldiers faced before they got feet down.
And to answer the answer about back up sights on the raid, well I can't say for sure. But I did ask this friend about BUIS when on missions and he said that he had them on his rifle about 10% of the time. That 10% was when he was going to be on a daylight operation. He said the NV that they use makes it way too hard to use it. He said that he preferred using an Eotech on a riser because without the riser it was almost as hard to use with NVG as BUIS were. His backup (which was also his primary means of aiming for close quarters) was the IR laser.
He does now have BUIS on his defensive carbine. But he still uses a riser for his Eotech (old habits die hard