Chacham: Well, the Maskana is Tzarich Iyun. But everyone knows that you are allowed to wear Tzitzis in a bathroom. Thus, the idea that it might be Assur just doesn’t work.
(Interestingly enough, I found a T’shuva in the Tzitz Eliezer (somewhere towards the beginning of Chelek 21) that mentions that Tzitzis and Sukkah require a special type of Kavanah to be Yotzei the Mitzvah. It’s not just Kavanah, but you have to remember what the Torah said about them. Which would go very well with this R’ Shlomo Zalman. But it’s still impossible to say that it’s Assur to wear Tzitzis in a bathroom.)