Additionally,each person within the orgainization must know

这里 是 特殊疑问词组+不定式 作宾语的 结构,不是宾语从句,但是可以同义句用宾语从句：
...must know what tasks 【they should】 perform in order to ...
类似的以 特殊疑问词组+不定式 做宾语 的例子很多嘛：
I don't know what to do.=I don't know what I can/should do.
I don't know how to do it.=I don't know how I can/should/will do it.
I don't know where to go.= I don't know where I should go .

这里不是从句，而是不定式做后置定语的情况

不是，what引导的是一个名词性质的短语，做know的宾语，to perform是不定式修饰tasks

这里并不是从句，是what+不定式的名词性结构，类似的搭配还有how to do, what to do， where to go这样的搭配

what tasks to perform不是宾语从句
what tasks做know的宾语， to perform做what tasks的定语
例如 Please give me an apple to eat.
其中an apple to eat 与 what tasks to perform结构相同
what引导的是一个名词性质的短语，做know的宾语，to perform是不定式修饰tasks