I figured I'd replace it because it looks like the string isn't being held in place by much in a few other grommet sections. I'm not sure how that affects the string tension and overall playability. But you're the second person to tell me the frame won't be harmed, so I'll give it a whirl!
Don't worry at all about the effect on the racket, it doesn't make any damage at all. I'm playing with my racket (Dunlop biomimetic 100), many damaged pins in the grommet, and this happened many times with me, grommets are not cheap
(specially PS & vintage rackets). And by the way, Prince has many rackets that comes with no grommets, different design.
It will make that annoying sound when hitting a ball, metallic sound, so I recommend you to use 2 vibration dampeners, one left, one right, on the same line of the damaged pins, or use one of those long warm shape dampeners to cover all the "main" strings.
PS: Try to replace just the damaged pins, I did this to my PS85 (Taiwanese). Be sure it's the same size: length & thickness.