No, it is CRUCIAL to use quality baking chocolate for this recipe or your filling will be grainy.  Set yourself up for success by using QUALITY baking chocolate such as Ghirardelli brand.  Baking chocolate is cooled, hardened chocolate liquor with a high percentage of cocoa butter because it’s intended to be baked with and therefore melts beautifully when making the filling, whereas, chocolate chips contain less cocoa butter and will not melt seamlessly and can leave you with stubborn chocolate pieces (i.e. they’re not suitable for melting).