Hi,

There is a ton of threads about RAF, i know this because im one of the posters..
Anyway, the way you want to do it if you will be bosting is: Account A (High lvl char) this Account needs to be unlinked. So you start Account B and refere Account C.
About the mount though. i think you only get the mount on 1 account this way. (Account B)

Here is a link to the wiki also you could read.