[Mardagg]

i watched the battle.
If you click on morale of one of your vamps you will quickly see,that it was not your dominion.
The thing to consider when battling with immortals is,that the turn order for this is important:

1. preaching happens

2. battles occur

3. dominion is spread by temples

so...if you have positive dominion in the turn you order to attack it might change due to preaching priests,renember that these can be stealthy!
Likewise...if you see you have positive dominion after the battle in the province,it might be because your dominion spread to a positive number just AFTER the battle.