Then definitely leave them at home. If you survived last year without them, you can survive this year. Just hearing that you got attacked and pinned down makes me very, very nervous for the safety of your pets. Rats are not durable creatures when it comes to going up against a human being. We've got at least 100 lbs on them, and most of us many more than that. Even turtles get killed when stepped on.
Seriously, thought! At con meetups, people will be more inclined to want to feed them and pet them, I'd bet!