From personal experience I highly suggest you forego attemtpting to keep salamanders in a dorm. The temp requirements are hard to meet, dorms are very noisy and thus stressful on the animals, roommates can be less than trustworthy, and you will have to move out of the dorms in the summer (and perhaps even during winter and spring breaks depending on the dorm). I lived in the dorms last year and paid dearly by attempting to keep sals at first. I learned from my mistakes, however, and sucked it up and decided not to keep salamanders for the year. I am very satisfied with my decision. Now I live in a house, can provide a more stable environment for my animals, and even have more room.
Another thing to think about is that many/most dorms will not allow animals besides fish. While it depends on your RA whether they will bust you for this violation, in my dorm I found that most RA's will become your friend, however, they will maintain their job and WILL write you up if you violate some the rules, especially the more serious ones (which keeping animals besides fish seems to be, as they believe it is a health hazard).
My personal opinion is that you should not attempt to keep salamanders in a dormitory. It is stressful on the animals as well as you. Dorms are too active and too hostile for salamanders. I suggest waiting until you move into a more stable and less stressful habitat before keeping salamanders.