If you have two toons in two separate guilds, and each of them are in separate guilds, then MonolithDKP completely jumbles all of the tables for every toon together. Each toon should have its own independent storage table for guild members so when you type /dkp you only see guildies of the currently active toon.

Bonus: have a "toon switcher" option to see the dkp lists of alts.