Definitely should just take out the trees completely or else just turn them into a mob and make them drop..
Give zombies higher damage where they should kill before rock is mined by lvl 30 warr (bit harsh needs be done) or just make bichon mines very hard to get good ore and make a serpant valley mines or something that has much harder zombies but good rate of good ore..
Finaly, obviously these bots have mains or else there just nobbin gold sellers but cant u trace down who they traded with to see if they have a main and ban that.
Theres always a way to get around a ban you see this happen all the time on other games with programs to disguise there ip's as well
Genuinely id say u have to get brutal with the fun relaxing things coz of these game destroyers