Thank you. I guess that is a good way to handle it.
But I still need to figure out how to set the address it lowers the balance from,
so it takes it from the right account.
Currently it seems it is picking the BTC from the entire wallet, not from
let's say label "John", who is sending 2 of his BTC to "Peter".
EDIT: seems like the "move" command might solve my problems here inside the same wallet working with accounts.
Will update once tested.
Update:
sendmany '.$fromadrlabel.' {\"'.$toadr.'\":'.$amount.'}"',
and
move "'.$fromadrlabel.'" "'.$toadrlabel.'" '.$amount.'1',
did the trick for me. Thank you for helping to understand