I just did another test. On the same computer, I monitored the install of Free Office. After uninstalling it, HiBit only found leftovers from Free Office.Probably the reason why it's always recommended to remove Antivirus installs only with their original uninstaller. I believe uninstalling an antivirus with any uninstaller (more specifically using advanced scans) other than their original uninstaller/windows uninstaller must be used with extreme caution. This is possibly because of serious false positives that are bound to happen due to large number of registry entries an antivirus might interact with.
Hope this isn't the case with regular software uninstalls, at least from my testing. Finally maybe the new installation monitoring feature needs to mature, and it could happen in due time.
I've had no issues when using Total Uninstall to uninstall antiviruses. In theory, it shouldn't matter what software is being monitored, as HiBit is using snapshots of the system, rather than actually monitoring what changes happen to the system, which is IObit and Comodo Programs Manager do.