There is no evidence that tarot was used for divination at the time of Rudolph (edited to add - sadly!). I've looked into this too, and although Ripellino briefly refers to tarot readers in Magic Prague he backs this up with nothing - I take it as a romanticised description, not fact. We are currently researching Lasenic and Universalia, and interestingly (and I think significantly) their tarot knowledge seemed to be based mainly on Papus and Wirth (Lasenic studied with Wirth) - i.e. they were drawing from the French occultists, not from any local form of divinatory cards.
Of course, there was scrying, astrology and other forms of divination a-plenty at Rudolph's court (and very interesting in their own right), but I've found no evidence that cards were used in this way.
Tangential perhaps - the Czech Marias cards ARE used for divination. I had assumed this for a long time (as local oracle cards follow a broadly similar structure) but only recently confirmed it when I walked into the shop of someone we know to find a Marias reading going on - first time I've seen this and the method looked interesting. I will find out more when I can find the time. However, this still is unlikely to date back to Rudolph's era.
