"That is not judged by us."
Translation:Itu tidak dinilai oleh kami.
I think some context about 'itu' would be useful, otherwise the sentence seems incomplete
I don't think context is necessry.
The sentence is complete as it is.
You can replace 'itu' with whatever you like.
for example "(Masakan) itu tidak dinilai oleh kami". In English it would translate as "We did not rate that dish".
You're translating a passive sentence ("dinilai" is a passive verb) with an active sentence.
Translating an passive sentence in a active sentence is rejected in this course.
It's a different sentence structure, using a different verb.
"We did not rate that dish" = Kami tidak menilai masakan itu. <== active voice ("menilai").