How do I beat Zombie Hug-a-thon 2/9/2017

The gimmick that the developers thought of for Valebrains Zombie Hug-a-thon, 2/9/2017. Fails because the zombies go to the upper lane too & end up popping the Potato Mines.

I ran out of money to retry, &  chances to watch Ads to retry.

Also, My Epic Quest keeps resetting to 0 Steps of progress. I completed 2 Steps & it reset to 0, twice.