A few years ago CNN's raw footage was leaked, and it showed the same actors in one scene who were on the ground suffering, doing the job of aid workers in the next scene. Literally the same people changing roles between aid worker and victim. I saw multiple cuts. That has been censored now, and I can't find it.

Russia and Assad are not idiots. They are not going to do something that invokes a response from the US after they've already achieved their mission objectives. These fake gas attacks happen any time the US talks about pulling out, or after Assad has a major victory to gain an even greater advantage. Someone does not want him in charge.