So Bohemia has a perfectly viable, if female heir? Well, then I dont see the problem. Elizabeth can be betrothed to somebody... of course, I guess Anne could also remarry, and if she then gets a son hell be prior in succession to Elizabeth... (But not if she further only gives birth to daughters, in which case Elizabeth as oldets would remain heir)
But that is my doubt: did Bohemia ever had before a reigning female monarch? And, as the crown was an elective one, wouldn't the Bohemian Diet rather elect other noble instead of making her the Queen? And in the case that she is accepted as Queen, would she become the only female ever to be an Elector of the HRE?
I can see a possible husband be elected as king. Well, officially Ferdinand was elected by the Bohemians, the Hungarians and even the Croatians in different elections, and his position was conquered because he was married to her. But would a female really become Queen of Bohemia and/or Hungary in the early 16th century?