We don't get too many calls on cascading older products but this one was tricky. We know that if your license is on Subscription, you can access the current version and 3 versions back. If you have the Maya Creation Suite 2014, it should allow you to run Mudbox 2014-2011.
The following behaviour will happen:
1. Install Mudbox 2011 using 498C1 Product Key.
2. Setup a license server with Maya Creation Suite Premium 2014.
3. Launch Mudbox 2011 and there will be a 0.0.0 error.
The 0.0.0 error typically indicates that the server is working correctly but there is no license for it on the server.
Just a note, if you have the Maya Creation Suite Standard 2014, it will run allow you to run Mudbox 2011. In this instance, you should upgrade to Mudbox 2012 if possible.