If the route you are assigned to run is your primary route, NO you can NOT be bumped from it, unless you accept to run another route. If there is a need for you to run another route instead of your primary, and You accept to "help" by running the other route, your pay should not be lower than your primary route's evaluated pay.
If it is another of your matrix choices and the bumping Rca is higher in the matrix list for that route, then yes, you can be bumped. If the 5/1 aux carrier's primary route is one that you have been working but is the 1 of the 5/1 aux, then it belongs to the aux to run.