Thank you very much for replying.

Yes and No (the item is not in his inventory either). Also, my inventory was not full.
As mentioned, in the messages of given rewards, the mount was not listed.
Also, I had performed many google searches for an explanation or recommendation and I was not able to discover any information. I spent quite a bit of time with my inventory and character, trying to identity the cause and again, could not identify one.
It has been a very frustrating puzzle.