Iamxourtingdeath
I say that you better put Kaguya in the chat group, she is the final villain and your future lover, her only way to strengthen herself would be the chat group, the tablet would not help her much since she was sealed for years and does not know many things. Madara does not occupy too much of the dimensional group, he can perfectly improve his strength with the tablet, unlike Kaguya he knows too many things about the Shinobi world and if apart from that you put him in the chat, then he would have too much power if you add the tablet. from marvel you could put hela the sister of loki, she is a very strong villain and it is a pity that from the beginning her destiny was betrayed by odin, being sealed in a dimension of death and only so that when she finally freed herself she was killed for a prophecy (it's basically a kaguya 2.0) and I repeat, I say that madara does not join the chat for the simple fact that he already has a way to improve his strength, being the tablet, giving him the chat apart would be to make him too op and basically the same as the main character by having the same " golden fingers" than the. and finally this is just an idea: why not change the chat shop? make the prices for the other members slightly higher than their original price and that those leftover points go directly to the pocket of the main character, they would not know it and you would win free points from them
author since Madara is a genius, have the process when they are being fed by the chakra of the divine tree turn them into white zetsu. Otherwise If it's a intentional purposes, Madara can change the jutsu and the palm can go forward. But since Madara can also capture every human in a genjutsu at once he might be able to do it manually.