Glad you get somewhere, If its show up in HA integration then it definitely connected, Easiest way is use SmartIR custom component. Learning code in HA is complex and time consuming. Go have a look there and see if if your device brand is listed. They have all the common brand LG, Samsung TV, Daikin Aircon etc.
at this point you can try to get it in Broadlink app again. see if it can discover the device when your phone is in the same wifi. Wait at the last step when you choose RM4C but dont choose anything just wait few minutes.