A few points:
My last mods to the Lua file would have no useful effect, so my bad. It's been a while since I looked at this code so my memory is a bit out of date.
No "RF child" is produced. You get one child per physical Broadlink device (if they are known to the plugin). That child handles both RF & IR, as the sent code is either an IR or RF code.
I see three IP addresses in the logs provided, which makes understanding the log a little tricky. Regardless the plugin knows the physical devices by their MAC address, so the IP address can change around. Have you fixed IP addresses for the BroadLink devices?
I probably need to make the logging a bit clearer on what's going on.
On the aircon - the BroadLink protocol is not published and they change it from time to time so reverse engineering is always on going.
On the RM4 Pro - this tells me its been discovered OK:
{"a0:43:b0:18:de:8d":{"blInternalId":"00000001","blKey":"a7c5df0a9133f188c982a56dc8bcf9df","blDeviceType":25755,"blIp":"10.1.11.20","blDesc":"RM4 Pro"}}
I assume here that the MAC listed above is the MAC address of the RM4 Pro? There is no list of found devices in the plugin's GUI representation (there probably should but I didn't do one). The json above is the "list" and it looks fine. Once a device is defined in the json it stays there; even if the device goes off line (for whatever reason) and therefore not discoverable. If the IP address changes the json is updated to match.
The final problem is the "cloud bit". Some of the newer devices get this bit set when the app is used with the device and it causes issues. I have no experience of any of this, as I my devices don't have it. Need to read the thread at the other site, that talks about the reset/pairing procedure to avoid problems.
Also is this is on a Vera or openLuup?
Try relocating the Broadlink device closer to the WiFi connection. I still maintain the comms may be a bit flaky. If you send any IR code to the device the log will show what's happening and you can use a cellphone camera to see if the IR is coming out of the RM4 Pro.
I have no plans to get this to work for the aircons - looks like a major effort; especially if you have no hardware to test the code on.