The condition of Dylan’s nails ought to come as virtualy no surprise to anyone who’s ever met him. They’re clipped short, kept clean when he has the time to do so, and frequently scartched from hitting too hard against something. It’s one of the few vanities he lets slip into his character as Rhodes — keeping his fingers clean is simply a part of his daily hygiene routine, even if he considers it as a rather irrelevant task. Those who knew him when he was still a smoker might’ve briefly seen him with stained nails — though very, very rarely.
( And as far as the nails made of metal goes, Dylan rarely uses them in shows: fakir tricks went out of style roughly one thousand years ago, and Russian Roulette isn’t really his forté. )