Did carbon monoxide kill people during the Duma chemical weapon attack?

EAST GHOUTA, Syria – With tens of people undoubedly being killed in an attack in East Ghouta’s Duma blamed on chemical weapons and perpetrated by the Syrian government, despite no evidence being provided, another theory has emerged suggested those killed was by carbon monoxide poisoning.

Twitter user @tarek_oo7 made a case why in a series of Tweets.

“One of the possibles of what could have happend in Ghouta and the dead families cramped in undergroung shelter is carbon monoxide poising.
It is possible and i will explane why in the following thread:” he said from Twitter.

1- Below pictures is taken from “rebel” tweeps calimg it is the victims in the under ground shelter. Notice the wood buring stove and the carbon fire marked in red. pic.twitter.com/h5HW2ANu9p

— طارق (@tarek_oo7) April 8, 2018

2-Here we see a ved posted about the ghouta today , notice the jurno is going deep underground to a shelter, and notice he is not weering any mask. pic.twitter.com/E75UHjXrpG

— طارق (@tarek_oo7) April 8, 2018

3- The same jurno arrived with no mask first and the bodies all over the place yet another white helmet guy in the same position and same (notice the back ground) place later with full mask to claim the place is full of gases! pic.twitter.com/vFyR4ULArF

— طارق (@tarek_oo7) April 8, 2018

4- This is important : As for the white foam on the victims mouth , similair accident of carbon monoxide poising happend in the UK where the victim was found dead with white foam around his mouth?? pic.twitter.com/ncfJGXnGg6

— طارق (@tarek_oo7) April 8, 2018

5-Carbon Monoxide poising is serious, below is a chart explaing excately why it happened and the symptoms, main reasons using stoves, burning fuels in enclosed rooms ,and we have seen these ppl where under ground and we saw the stoves and the black carbon all over the place pic.twitter.com/wSULZiDsdl

— طارق (@tarek_oo7) April 8, 2018

6-Iam here just postting a different logical scenario of what could have happened, no one is sure, no one have access to these victims to take blood samples and confirm anything, all online tweeps from the terrorist side is exploiting this tragedy.

— طارق (@tarek_oo7) April 8, 2018

So what do you think?

Could his theory have any validity to them?