Authors CurseForge

For Sindragosa / Putricide encounter, the boss are tagged as "elite" and not "boss" like DeathWhisper.

So to track them you have to add them in the WhiteList :

    HeadCount:addHashValue(HeadCount.BOSS_WHITELIST, L["Professor Putricide"], true)
    HeadCount:addHashValue(HeadCount.BOSS_WHITELIST, L["Sindragosa"], true)

For the Blood Prince, you surely have a raid members that kills a spider or anything else, so the combat start event is triggered and HC start looking at all targets of the raid to detect the current boss event ;)