While it is highly likely that killing the process on the others two systems will not cause any problems, being that we are dealing with a database it is better to err on the side of caution.
1. Stop the Vertica cluster through adminTools
2. Run 'ps -ef | grep rc' to see if the rc script is still running
3. If it is still running you can kill -9 its PID
4. Start the Vertica cluster through adminTools
The likely cause is that after patching, the admin team initiated the S99verticad start command on all 3 cluster nodes and as Vertica only needs a start command from one, the other two commands sat lingering.