Titanium can be easily refinished, even proper deep dings. It's just that Tudor won't. Using a bit of scotchbrite to remove surface scratches works, but it's hard to properly match a factory finish - you tend to see how someone has tried to do it themselves in sunlight.
But Omega (if their service dept is not being it's usual rubbish self) and Breitling have had no problem refinishing serious marks on Ti, but it's just that Tudor are weirdly and pathetically refusing to refinish the Pelagos. I have a suspicion why, but it's just a suspicion (to do with how, or who, makes the cases). But hopefully now the Rolex empire have used Ti in another watch they might change their tune.