Alice's most valuable clue is green to Bob. This would be a Play Clue on the green 4 and initiate a Reverse Finesse.
Unlike the previous question, the Reverse Finesse will work because Cathy knows that her yellow card cannot connect to a green 4.
Alice could also clue number 3 to Cathy as a Play Clue on the green 3. This would also "fill in" the yellow 3. But it would only "get" one brand new card instead of two brand new cards.