“Heroes of Might and Magic V: Tribes of the East”

This... I have a question about "Lords of the Realm." When playing the final mission in the Orcs campaign ("In Honor of Our Fathers"), there's no way to attack the city of Shahibdiyya, which needs to be captured according to the scenario. The entire map is open, all other cities have been captured, but when I try to attack Shahibdiyya (a powerful mage is stationed there), my hero simply stands at the city gates, and the attack doesn't initiate. If I leave the hero there until the end of the turn, the computer tries to move its second hero (also at the gates), they end up on the same tile, and the game crashes. This is frustrating because I generally enjoy the game, but I can't progress in the campaign.

I have a licensed copy of the game, but it's a translated version. When I install the game on another computer and copy the save files over, the same problem occurs. Can you please advise if there's a way to fix this? As far as I understand from the website's information, there are no patches available for "Lords of the Realm" yet...

Also, if I buy the English version and copy these save files into it, will that help? Will they even work?