How to win on Might & Magic Heroes VI - Haven - Something Is Rotten campaign map

I've tried the map three times already and lost each time. Played on easy difficulty always.

I tried following the conflux advice but the enemies are still eventually overrunning me with superior forces.

Didn't take the fort to the south so that the south enemies remain passive until I can take out the enemies in the east. Done the griffin quest as soon as I cleared the main base area.

After that I went directly for the east enemy but their forces were already superior to mine. I think danger level high. And there was no way I could have taken 2 high level fights one after the other to take their castle.

I was forced to retreat to my castle to build my forces but as time passed I got attacked by both enemies and in the end, after multiple fights, they won.

It is pretty obvious that the more time passes on this map the less chance of winning there is.