I was wondering if the microgroove golden records they put on the Voyager spacecraft, along with instruction on how to decode it, were first put to the test with the subjects most likely to decode them, i.e. humans.

I would suppose they were, as Carl Sagan takes the complementary stance in Contact to have humans decode an alien message, but incidentally the alien message mentioned looks quite too close, both in methodology and content, to what humans sent a decade earlier, non-fictionally, on the Voyagers.

So, did they test whether or not they were decodable, and was a 100% interpretation achieved?