We had the same experience, except we looked for MVM servers in the Servers menu, and succeeded. It is indeed great.

Finished my first mission, Coal Town and Decoy are hard as fuck.

I found out that the Fan O'War for the Scout is an amazing weapon for this mode. Try using it on Tanks, Sentry Busters and Big Robots.

You hit something and it gets Mini-Crits on it "marks them for death" so it's a bit like the Jarate only it's better because it's a melee weapon and once Mark runs out, you just have to hit them again.