I agree with the panel that there's no appellate jurisdiction over a nonbinding recommendation made by a district court regarding where an inmate should serve his sentence. It's nonbinding. It's not part of the sentence. No appeal.
Given that, I'm not so sure it makes sense to have the first part of the opinion actually decide this question. Which the panel here does. It seems particularly anomalous to tell the district court that it has no jurisdiction to amend a sentence as part of your resolving an appeal over which you have no jurisdiction. It feels sort of like a pot calling the kettle black.
Which isn't to say that the panel can't say whatever it wants. It can. The lack of jurisdiction doesn't stop you from making whatever observations you'd like. Including, when you're on the Ninth Circuit, from saying how you'd resolve an appeal were you in fact to have jurisdiction.
But don't forget that the district court is similarly unconstrained. The Ninth Circuit decides (in dicta) that the district court wasn't authorized to amend the sentence to recommend a particular placement. But that doesn't stop the district court from recommending a placement outside the actual judgment, and the Bureau of Prisons appears to give deference to placement recommendations from the sentencing court regardless of in what document such recommendations are made.
So just like the Ninth Circuit can say what it feels, so can the district court. And while both lack technical legal significance, both have profound practical effect.
Which is what matters.