Hi Aria,
I may have to disappoint you but I think you may be slightly on the wrong path, ChipChop is not an MQTT broker and doesn't support MQTT.
The confusion is probably from the fact that at the moment the library 1.43 is using MQTT as a data transport layer but that was done only for compatibility reasons with some Arduino boards as the WebSockets proved to be too complicated/heavy for some boards and will be replaced soon by a much more advanced protocol.
On the server side absolutely nothing of the MQTT logic is used, just the "payload" part of the packet which is then processed in the same way as websocket data.
Basically if you try to send standard MQTT messages to a ChipChop server there is a good chance your IP address will get banned and you won't be able to connect your devices at all permanently (unless you contact me direct and I will have to mess around with the firewall to take your IP of the blacklist)
MQTT is very very very old protocol and has become popular in IoT because it's very "cheap" for the cloud platforms to implement (and easy to sell to users if you throw enough money into marketing) . Ultimately all the hard work is passed to you and your devices , an mqtt broker server is just a publish/subscribe switchboard and doesn't do shit with any logic, you have to hardcode and handle everything on your ESPs.
ChipChop works differently, it acts as a big "co-processor" for your ESP so you can do a part of the logic on the server side without re-programming your micro-controllers (that's the role of Actions, Alexa, Virtual Triggers, groups etc)
This behaviour is very costly on the server side, not just in processing terms but also makes the software engine a heck of a lot more complicated to write and maintain than a Mosquito MQTT broker.
Anyways, there are ways of creating a "bridge" between MQTT and ChipChop if it's absolutely necessary and there are some here that have private ChipChop servers where such a bridge is used (for example bridging direct communication between Node-Red and ChipChop and also there is one for Shelly devices)
It can also be done on a small scale directly on an ESP, for example, I've made the code for one of the ChipChop users to have a communication between a Z-wave sensor, Home Assistant, ESP32 and ChipChop and it works no problems.
By the way, I can't figure out which ChipChop user you are? Have we talked before over email? (please don't post any personal info here, maybe just the last 4 characters of your uuid to refresh my memory)
So yeah, sorry to disappoint you but if you like the way ChipChop works and you must use MQTT please talk to me and I will see what I can do to find you a solution.
All the best
Gizmo
