1. That Vault-Tec launched the nukes
2. That Cooper is Vault Boy
3. That NCR was nuked in 2177
4. That the Enclave Dog is Dogmeat
6. That's not the Prydwen
7. There's any good guys in the show
1.
What can I say?
I think I read on some terminal that they heard the planes coming.
Somewhere, maybe the Avellone Bible, I read that it is not known who dropped the bombs first. But I also read that other countries, besides the USA and China, then started to drop theirs. It is not specified which ones.
It remains to be said that Vault-Tec did not need to drop 10 or 100 bombs/missiles, one would have been enough to then start the tennis match between the states involved in the main conflict.
It remains to be said that so far only 2 atomic bombs have been dropped on densely populated areas and in the Fallout TL they were the same as in ours. The USA. so it is possible that VT started it.
2.
Cooper was the initial face for VT's campaign as Vault Boy, then upon discovering the company's plans he either walked away from them or was pushed away, going broke and ending up doing birthday parties.
So VT asked Hubris Comics (I think) to create a very optimistic mascot, based a bit on the Cooper model
3.
I don't know for sure, in 2277 I was in Washington DC looking for my father.
I haven't played FNV in a few years but I don't remember anything about it. The courier is given the ability to nuke the NCR in the Lonesome road DLC... the one in the divide. But that's 2281 or so.
4.
Any dog can be Dogmeat, just as any St. Bernard dog can be Beethoven and any German Shepherd can be Rex (the dog from the TV series, not the Kings).
It's just a name (even though his real name is a code for something-4), for obvious reasons it can't be the dog from the first fallouts and certainly not the one from 3 and 4 set on the opposite coast.
6.
Maybe there were more than one Prydwen, like Prydwen 1, Prydwen 2, Prydwen 3, ecc...
7.
No one is ever completely good or completely evil. Not even Marvel's Thanos is completely evil in reality (let's leave aside the movies).
Lucy is the person who comes closest to the good character par excellence, at least at the beginning. I also think her naivety serves to make her appear so. But that's because she spent her entire life underground. But I think it's also a narrative choice to show how the wasteland changes you profoundly. The same change that happened in Cooper/The Ghoul in much longer time. Even in the movies he initially didn't want to kill his opponents. Clint Eastwood didn't have that problem.