No, not needed for the RMC3 to connect. Just need SSH turned on and configured properly in your module. You can also try changing the SSH connection type to "Unsecure" in the Parameters if you simply want to test your connection and troubleshoot the key later.
Crestron also just released a free program for the RMC3 that you simply configure via an Xpanel.
I assume you are a dealer of course and have access to this.
