Russia is not that crazy to comply with that sort of intrigue/suckering.
I see no advantage to Assad for using chems.
Why does Putin want to test Trump when he has basically already been neutered by the Obam leftovers and the establishment. He could have at his leisure sat back and laughed at appellate court justices shitting on Potus.
War tends to unify political opponents.
I don't see any upside for Assad in using chems. Two or three barrel bombs would have been as effective.
You don't see the upside for Assad because you have not considered the stratigic objective. He wants to make sure people are terrified of him and that people understand that there is no hope of outside intervenetion.