Welcome, Scott. From the Cajon Pass. That is one pretty plant! I had never seen one before. And looking it up there is very little info available.
But it did say not to water. That trunk it has will probably have stored plenty. Leaf browning in succulents
is often a matter of root rot or too much water. I would leave it alone and make sure it isn't a natural thing happening. It could be you will soon see new green growth beginning in the middle of the top of it and that set of leaves will fall flat against the trunk.
Good luck. I hope it makes it to be so beautiful for many more years in your yard.