Mqtt monitoring / syncing states, need bit of help

General
17

Some initial notes:
The return false should be return null. I have no idea what return false will do. Perhaps it has the same effect as return null but I don't know.
If you do return [[ra,rb,rc]] then it will send all three messages to the first output, so you only need one output.
The Join node should be set to wait for three messages, you still have it set to wait for two.
Does it work ok for you if you disconnect the mqtt in nodes and just use the inject nodes? If so then the problem may be caused by the fact that when you send a command out then soon after there will be a status command back as a result of that change, which may be messing up the algorithm. So possibly something like this happens
Assume all switches are off initially.
Suppose switch A goes on. This will trigger On messages to B and C.
An On status will then come in for B. this will trigger another On for C.
Finally the On status will come in for C. In fact there may be two On status messages for C, it depends whether you get a status message when you send a command to switch it to the state it is already in. That will be mopped up by the RBE node however. I guess the fact that you put the RBE in suggests you have already seen that situation.
Something like that anyway