Auto-translated
She's choosing the city correctly, nothing happens - when I hover the mouse over the tavern, a highlight appears and disappears after a second. So, I suspect that the program is mixing up the buttons or something like that.
I just load the save (with the city window open, of course), launch the digger, select the hero, the current city, and the slot where to dig, and click the green arrow - the digging starts.
Военное дело просто и вполне доступно здравому уму человека. Но воевать сложно.