The biggest trick the devil ever pulled on smart people is to convince them that there are no conspiracies. ok

On your point in Douma, the deal to evacuate was reached two weeks ago (about 10 days befoe the alleged attacks) https://www.google.com/amp/s/mobile.reuters.com/article/amp/...

So it's more likely that the attack is false flag last ditch effort one. We all know that the civilians that the "rebels" hold are hostages. Even the article you cite says this much.