Hello!
If I understood well your question. I will name those bosses from my own experience, I considerer have a Invidual loot independing of your lvl/damage or participation, where the loot is predominantly random.
There is no such thing as "bosses that give individual loot, independent of your participation". The very premise of the reward container system is the participation system. The requirements for a participation and minimum participation varies, but there's always a requirement. If you want a list with all bosses that use the Reward Container system on TibiaWiki:
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