Is there a correlation between cellulitis and metal implants?

Probably: Yes, it is quite likely from superficial contamination and repeated trauma or from bacteremia, that subcutaneous or intradermal implants are associated with increased cellulitis.

No: Certainly anything foreign to your body can elicit a reaction such as inflammation or infection, and the implant can become infected and as infection spreads superficially you may see cellulitis, but otherwise no specific correlation.