(going to reply in English for the benefit of other users)
Croatians don’t have the same stigma in western Europe that we do. In the minds of German/Austrian/French/etc racists, the Polish, the Bulgarians and us Romanians are lazy, criminal welfare thieves.
Insofar as Russia is involved in the Schengen decision-making, they’re likely just attempting to deepen existing fault lines and create more instability. In that context, I completely agree with the pro-Russian eurosceptic angle.