I would not be surprised. After Ivan the Terrible, Russia was divided and chaos broke. Later the Soviets probably tried to hide it. With Russia more free, I expect the Russians may want do more work on it. 'key' to Tsar's secret library'
Oh, well. It cannot be truth
The true story sounds so: His library was in the Kremlin until distemper in 17 AD. Then all books were looted and a part of them is completely missing but some of them were collected in the State Historical Museum in Moscow and i saw a few books from this library.
The real library had about 800 books. They were brought from Byzantine by Sophia Paleolog (wife of Ivan III and grandmother of Ivan the Terrible). It was collection of old ancient (Greek, Roman and Byzantine) authors.
I pereodically read "Ivan The Terrible's library was found" or "we know where is this library" but all talks about it are groundless only.