Having more than one account per player in a game world is not permitted and is certainly punishable. In case you encounter suspicious accounts, you can report them through their in-game profile. However, if the rule enforcement team cannot find signs of breaking the rules on the reported account(s), no action can be taken. Evidence outside the game (Discord messages, for instance) is not accepted due to risk of manipulation.
I'm referring to what also Belisarius wrote.
Just because the IP address of two players is different means nothing nowadays, since everybody has access to VPNs, so I'm guessing most of these tech accounts are actually legit multi-ing, but using virtual machines and/or VPNs to avoid getting caught, if they're even doing it. Or yeah, maybe indeed a friend of theirs is playing that account so that later on their acquaintance can have their village, but still, this shouldn't be allowed, especially if they're from the same alliance, and magically they just quit few days before they're losing their village(s).
What I don't understand why is this allowed, it's clear as day and yet no action is taken?
Shouldn't fair play be promoted instead of this?