There's another example of apposition that the Klingon wiki doesn't mention.
http://klingonska.org/canon/1996-sbx-s26.txtDuraS tuq tlhIngan yejquv patlh luDub 'e' reH lunIDtaH DuraS be'nI'pu' lurSa' be'etor je.The sisters of the House of Duras, Lursa and B'Etor are constantly seeking a higher standing for the House of Duras within the Klingon High Council.(I underlined the apposition. Also, the sentence begins with a N-N-N-N-N construction. This has nothing to do with the topic, but I find it delightful.)
I suppose if you were worried about it being interpreted as a usual N-N construction, you could set off part of it with commas: sIlveSter, vIghro'. But if the context is clear that it's "Sylvester the cat" and not "Sylvester's cat", you'll probably be fine.