Yes. The entire panel needs to be painted correctly. More importantly, prepped correctly-making sure you follow whatever guidlines there are for aluminum panels.

If you want to fix it your self, you could just scrape off the bubble, sand the primer a bit, reprime, and touch up paint. There are also detail shops and places that touch up bumpers who use small airbrushes. Might be worth seeing about this-note this might be a temp. fix, as more bubbles might appear in other places. I would fight the dealer on this.