The article points to the report by the OPCW which confirms chemical weapons use in Syria. As inspectors tried to collect the data for their report, they believe Russian and Syrian forces were trying to prevent them from doing their job which indicates their ties to the chemical weapons test.
OUTLOOK: Moving forward there will be meetings of the international community to discuss the verified chemical weapons attack in Syria. Now that further reports are indicating Russia and Syria’s hand in the attack there may be more pressure on them. In the grand scheme of things, this report which verifies chemical weapons use will probably not have a big impact on the situation in Syria.
See article here: https://www.armscontrol.org/blog/2019-03-12/opcw-confirms-chlorine-use-%E2%80%99s-time-assign-blame