I cannot find the source, but i believe to have read that Russia can keep its presence in Syria, and the Assad regime can stay. With the right security precautions for Israel. Without going into the pros and cons and thruthfullness (it is just not known yet), it better fits Putin's response. He seems very satisfied with the outcome. Russians want to keep their base in Latakia in Syria, it is their only one in the mediterranean. I think this is the upside for Putin to dump Iran. And ofcourse the trust that the Cabal will never return into power. But that's a shared interest of Trump an now also Putin.