War replays will never be 100% accurate because they aren't actually replays. The game takes your deployments, rallies and tactics and uses that info to approximate what you did in the game engine. To save thousands, if not millions, of replay videos would require insane amounts of server space. No mobile game with replays has actual replays. This one just has more moving parts than most so the butterfly effect tends to be greater.
Now these replays that are completely off or show all manner of extra troops that shouldn't be there are probably cheaters. Though Nexon will never admit to that. Security is expensive and this game is pretty low on the BHG pecking order these days. If people end up spending money to compete with obvious hackers then that's a net positive for Nexon rather than investing time and resources fighting hacks. Integrity be damned. I think that's been proven by the 18 month Road to(Nowhere)Better World War Matchmaking among many other things.
As for CWA attacking globals? Between the lengthy upgrades, lack of workers and player attrition I'm guessing there simply aren't enough atomics for CWAs to attack. Hence The Winter of Ages. Guess we'll see by the end of January if this changes.
Of course one of these mods could do more than issue a vague statement and squash such speculation, though I wouldn't hold my breath. They don't work weekends afterall. Guess we'll see next week.....maybe.