I thought so too, [that JWs wouldn't go for catholism], but there are many that have a very catholic view.
For the record, I'm a catholic and I have never been a JW, but my bro was baptised JW some 20 years ago or so and he always would tell me how he'd eat catholics, protestants and mormons for lunch.
And for many years he had me stumped with his well worked out sales pitch. I was the typical catholic insomuch as I believed that the catholic church was the truth, but once he started throwing scriptures and meanings at me , well, I was not prepared to defend my faith and I certainly failed in seeking God's will. Although he got me to abandon my catholic faith for several years, I still never believed that the JWs had the truth. I dunno, but from the get go I never got a good feeling from them. It was later confirmed when my brother didn't help to tend to our grandmother before she died. Then couldn't go to the funeral. Then the same thing for 2 other grandparents. Ofcourse such choices led to heartache for our parents [and still contiunues today...damn, he's dumb].
Later, I had a very personal gift from God that prompted me to read scripture [as well as doing many other things] and then, after some time, I could answer his questions with an amount of confidence. Later, as I started reading some of the church fathers positions I knew that they very much favored the catholic position and had written extesively about their beliefs and practices.
Ultimately, the more well read one is on the bible, the early church and the beliefs of the church fathers, the more likely they would drop the WTS and embrace Rome...obviously imho.
respecfully,
dc