So most dorms don’t want you using your own routers because a bunch of student routers causes A LOT of inference.
You should probably reach out not to the dorm folks but the university networking folks as they’re the ones that will ultimately make the decision on whether or not to turn things off/disconnect you.
A cheap networking switch would probably be okay by them to get some more wired connections in your dorm room (routers aren’t really a great way to do that).
As a secondary concern, using a router will cause a double NAT for all your connected devices (universities don’t operate in the way ISPs do). That could cause some weird networking shenanigans, particularly for anything peer-to-peer like online games.