Lets see , we have a player work hard and pay tokens for his upgraded veterans and the other player take a retainer for free and effect his army like warcraft magic spell.....
I thing will be more fair on tournament to exclude them , that will balance more the game towards the skill of the player and not his retainers , especially those with lower rank that would like to involve in the community competition.
The retainers is a marketing tool to attract more players but for the realism short of of a strategy game that we all like I dotn feel is fair competition having my self penalize opponent enemy armies even if both sides can do the some,especially the negative retainers it like a form of cheating.