Hello,

Multisite-auth is really great plugin, unfortunately, it is not compatible with IP-Geo-Block.

The author say as following:
https://wordpress.org/support/topic/what-does-simulation-mode-mean/

Unfortunately, the result is the same as now. The problem is both have different methods. One has its unique session and the other depends on the WP standard session.

We tried a lot, but we failed, if you would like to help on this, it create much more opportunity for other people to use it.

Thanks.

Alex