Since I knew which secret areas belonged to each class ahead of time, that's something I never tried that during my beta testing -- not too thorough on my part.
However, I know for certain only the Sorcerer can reach his area, as magic is a requisite.
I'm not certain if the other classes can do what the intended class can do in Tower Bridge. What I mean is, while you can get there, you might not be able to access the goodies as the 'wrong' class -- OR, the goodies might be gone or empty, making it a wasted effort (because it's not for that particular class). I'll check it out when I get home tonight, as I've got to check something else out for Blackthorne...
Suffice it to say, you've found the B's secret area; the R's area is elsewhere...)