@Sebastian-Roth Thx for your help, Sebatian!
I commented out line
chroot_local_user=YES
And now everything is just fine about my FOG installation.
MB it makes sense to add into FOG wiki - that vsftpd option is incompatible to FOG.
Now I need to find a way to chroot one user but not to chroot other, but it is definitely not a FOG problem. (And, it’s simple)
Thanks again.
Best regards!