I think it very unlikely.
From a story standpoint, I don't see how he could do it. He's been stuck in orbit on a crippled ship for who knows how long. He no longer has an army, or any minions, to back him up, so far as we know, and his arsenal has likewise been destroyed. No one who has the ability to get him down is likely to do so.
From a writing standpoint, I don't see the creators bringing him back in the middle of everything that's already going on. Scrooge and family are going to be dealing with F.O.W.L., clones, the missing mysteries, and who knows what else. Bringing Lunaris in the middle of that simply for the sake of having him make one last appearance would feel like a total shoehorn.
