Since the brake lamp on only one side is not working, it should not be a fuse. You may want to check the socket that the bulb fits into - it includes some circuitry that can be burnt out as well. An easy way to check is to swap the socket with the side that works. If the light then works, you know it is the socket that is bad. If it still does not work, another possibility is that there is a computer system code - yes the lights are controlled by a computer in this car, and if there was a short detected (which can happen in rare cases when the bulb burns out in a particluar way), the computer will have disabled the power supply circuit. In this case, the memory needs to be cleared. A dealership can clear it with a manufacturer's scan tool, but that may be costly. An alternative may be to disconnect the battery for 30 minutes. This will clear other memory, including radio presets, but may solve your problem. If it does not, it may need professional diagnosis to identify other possilbe wiring issues.
See the 2011 Dodge Journey Troubleshooting page for more more helpful information on this topic.