What a pity, I hoped the user enjoyed the complete set. Well, if you didn't even dare to open the bag, maybe you can't solve your problem. I know that some humidity is into the bag (Between the inner bag and the plastic packing involves the booklet and cassette), but I'm pretty sure that the booklet and cassette are intact. Of course is possible too, that "juice" penetrated into the plastic packaging and stained the cassette and booklet due the long travel. But even though this has happened, the damage is minimal because I dried the piece of corpse to avoid that problem.
You have the choice to enjoy the complete set as it, or keep the booklet w/ cassette and put them in a new bag, and the rest in the trash... or get rid of the rotten meat, drying the packages.
In the worst case, drop me an email.
Regards