HealCommListener is a simple addon to check who is using HealComm or pfui's libpredict function.
/hcl to list all players in your raid who have sent messages on the HealComm addon channel. Players need to cast a healing spell before they are listed here.
/hclreset to flush the list of players using HealComm
/hclsave to stage saving the list of players using HealComm to a file on your computer. You can check it later or process it with additional software. WoW API does not allow direct control over files being saved by WoW.exe, so YOU NEED TO LOGOUT in order to complete the saving process.
https://github.com/bhaimerl/TWowLogAnalyzer provides tools to check the list of HealComm users against log files of who was healing in the raid.
Open an issue at https://github.com/Lyndrell/HealCommListener if this is not working as expected. This addon was a quick shot, so I most likely won't be spending lots of time on supporting it.