No, I don't find that plausible, personally. All that item does is confirm Stein was there. The accusation is long standing, was repeated in rolling Stone (from the Clinton camp) and other headlines suggest the GOP have been actively exploiting green votes to siphon otherwise democratic votes away.

There's enough shenanigans inside US domestic politics without invoking Russia.

(Stein strenuously denies receiving Russian funding btw, but she would say that anyway)